recaps of the top 'ask me anything' interviews from reddit and more...
We are Roman Mars and Kurt Kohlstedt here to celebrate the 10th anniversary of the 99% Invisible podcast. It’s a show about design and the built world we live in. Our new book drops today -- The 99% Invisible City: A Field Guide to the Hidden World of Everyday Design. AMA!

99% Invisible is a big-ideas podcast and website about small-seeming things, revealing stories baked into the buildings we inhabit, the streets we drive on, and sidewalks we traverse. The show and book celebrate design in all of its functional glory and accidental absurdity, with tales of exceptional designers but also everyday designs.

Show host and creator Roman Mars launched what was then a “tiny radio show about design” a decade ago, then broke crowdfunding records for journalism. He co-founded an independent podcasting network and did a beautifully nerdy TED talk on flags with over 6MM views to date.

Producer and book co-author Kurt Kohlstedt joined the show five years ago, but has been writing about design and cities since getting a graduate degree in architecture in 2007. In addition to working on episodes of the show, he also regularly writes articles for the website.

Our new book, The 99% Invisible City, reflects years of research and reporting about how cities work, exploring the origins and other fascinating stories behind everything from power grids and fire escapes to drinking fountains and street signs. It’s for anyone curious about design processes, urban environments, and the unsung marvels of the world around them.

To read more about the book, our upcoming live events or read reviews, check out our book page! Also: visit our subreddit at /r/99percentinvisible (special thanks to the fans who created and maintain that wonderful space!) and feel free to follow us on Twitter, Facebook and Instagram -- and if this show sounds like your cup of tea, be sure to subscribe to the podcast! Bonus: In our just-released episode, Roman and Kurt walk around beautiful downtown Oakland, California, telling stories from the book and offer a behind-the-scenes look at how we made it!


Note: Roman and I will show up at 2:30 to answer your questions, but meanwhile: ask away!

Update: Need to take a break and start getting ready for the live show this evening with Alexis Madrigal (details at - will try to check in later tonight and answer more questions!

October 6th 2020
interview date

Your podcast has made me appreciate the physical world in a way I never have before. A serious gamechanger over the past 3-4 years. One of my absolute favorite episodes was about hostile urban architecture. and the time Roman broke Mazda!

All that said, what is the favorite thing you have done during the course of your 99 PI escapades? Favorite story you wrote or person you met?


Ah yes - so Roman and I worked on that one together, actually, but he did all the heavy lifting! And the book it is based on is just great - Unpleasant Design, which has a dust jacket made of sandpaper (it scratched up my laptop!). We talk about hostile design even more in the book, too, including some quite recent and interesting stories.


How do you stop from falling into a rabbit hole while researching something? How do you know when something is enough? Do you have abandoned projects?


I ... don't (stop, that is). I follow rabbit holes as far as I can, like the W4-2 road sign. For deadlines, at some point you just put out what you have, but sometimes you also keep researching, and in some cases little things I posted short blurbs about became the basis for larger stories in the book, for example.


What's the physically smallest thing you've found to be the most important out of all the things you've investigated?


Huh, good question - the thing that comes to mind are breakaway bolts - they're these little bolts that attach poles to bases but are designed to snap off when a vehicles hits the post (to reduce damage/injuries in a crash).


The No Name brand episode resonated a lot with my Canadian compatriots.

Is there any other Canadiana you'd like to tackle?

(also thanks for the book. I just bought a second copy for my brother who LOVED that no name episode)


We did one on the Gander Airport, too! - I bet Chris (Canadian producer) has some more ideas in mind ;)


It always makes me smile that 99% is proudly produced in "beautiful downtown Oakland California." What's your favorite design story about Oakland infrastructure, history, or architecture? And more controversially - where's the best taco in the Town?


It's hard not to love the Cathedral Building which is near our office. I'm also a huge fan of the scramble intersection in Chinatown nearby. I even have the ornate pattern on a t-shirt!


I know I can submit this as a story idea on the website, but.. gun to your head: how do you feel about suburbia's ubiquitous fake shutters?

They always baffled me as a child- there were houses with fake shutters, and houses with no shutters, but I never saw a house with shutters.


I saw a hilarious tweet the other day of shutters framing garages - like, just, why?


What's episode, fact, or opinion has gotten your listeners the most worked up?

(Corollary on Reply All: lime wedges that are too skinny to squeeze.)


Oh, well, that would be this one. It managed to draw ire from a lot of sides.


What's your favorite story in the book? Also if we can hope for a post-Trump world, what role might Elizabeth Joh continue to have at Radiotopia? Or maybe she already does, and I just don't know yet.


I mentioned one in the second part of today's episode, so I feel like I should pick another that I also had to fight a bit to keep in - it's about how they deconstruct buildings in Japan floor by floor. It speaks to architectural durability, sustainability and improbably successful design solutions. It's called 'Unbuilding Codes' (in Chapter 4).


Is it possible to design towns and cities "cradle to cradle" it's easier for ghost towns to become natural landscape again, and urban areas whose design no longer fits the needs of the community can repurposed and re-developed sustainably?


I mentioned this in another comment, but in 'Unbuilding Codes' (really, that whole section on 'Heritage') in the book we do talk about everything from reusing buildings to letting them gracefully degrade.

Adaptive reuse is a huge passion of mine (I often recommend Stuart Brand's book How Buildings Learn) - I did my grad thesis on it and I've written a bunch of 99pi articles about it, too!


If you (Roman) had stayed in Chicago, what would the location tagline be? Kurt, what would you use for Minnesota?


"... reporting from my wonderfully temperature-controlled lakeside studio in Minneapolis, Minnesota"


Beyond having to work from home, what challenges and opportunities has the pandemic posed for your work on the book and the podcast? Are there stories you might not have considered otherwise, or approaches you might not have discovered? Have there been unexpected benefits? Have there been challenges you wouldn't have anticipated in March?

PS. Love my new challenge coin!


It has had less of an impact on the book, since a lot of the actual writing (not counting: editing, fact checking, layouts and so on) was far along by the time things started locking down. As for audio, though, not traveling to locations for stories is something producers have had to adapt to. I guess one upside is that now that we're mostly remote, we have people like Chris, Christopher, Delaney and Vivian working from all different cities!

Even things like sending a tape sync (someone to professionally record the 'other end' of a phone interview) is tricky. So ... more phone interviews and a lot of trying to figure out how to get interviewees to record themselves!


What's one thing you wanted to include, but couldn't find a way to make it fit?


There were so many. I wrote about some things that got cut here but I think blue stop signs would have been neat - it didn't reach us in time, though, so we ended up including it in our Highways 101 episode.


Bycicles are not cars and are not pedestrians . Some countries treat them like fast pedestrians some places like US treat them like cars. Why? ?? - a disappointed immigrant with the bike laws in the US of A.


I agree - overall, the US is not the best model of a cyclist-friendly country. There are exceptions, though, or at least: varying degrees of good and bad designs. Minneapolis and Portland are toward the top!


What assumption did you have about a design that turned out to be the most wrong/surprising?


This was decades ago now when I was working in residential carpentry/construction - I'd always assumed things like baseboards and trim were decorative, but learned they help cover stuff up (like where drywall meets the floor).


Where is the part of downtown Oakland that is beautiful? Or if you're referring to the entire downtown as beautiful, which part is the most beautiful?


I mean, Roman should probably answer this one too, but I kind of love the old oak tree in the park - I'm also pretty into the whole area of shipyards nearby, too (there's even a weirdly isolated little park if you drive out past them!).


Hi! I would like to know more about how you approach organising the structure of each 99pi episode (i.e its flow, content etc)? I have always found your style of storytelling very engaging, like how one seemingly irrelevant anecdote leads to the main story.


I'm not sure there's a one-size-fits-all answer for this. It's true there's often an opening hook of some kind, but how the narrative moves forward can vary. One example I like to cite of a non-standard but beautiful episode is Avery's The Pool and the Stream - then there are more interview-style episodes, mini-stories, we try to mix things up a bit ;)


Is there an email inbox just for suggestions/questions for new things for you to explore? Follow up to this: have you ever received a suggestion for something to research that turned out to have an unexpected story?


Our contact page has a 'story ideas' option in the dropdown - some make it all the way to becoming episodes, but other smaller ideas often make it into articles or mini-stories like the ones we collected in You Should Do a Story


Hey Kurt, just want to say I love(d) Web Urbanist back in the day?

Where do you get your urbanism/urban planning/urban design news? Any websites/accounts/channels you'd like to recommend?


Woah, thanks! WU was a big passion for a long time. CityLab and Curbed have long been go-tos for me, but I also follow a lot of urbanists on twitter (plus, people send me stuff, because they know what I'm into).


Thank you for making this, beautiful nerds.

Question for either of you-- when you were younger, what first made you question or wonder about the design of things(or how random things worked)?


I'm not really sure where that all started. My earliest design-related memory was from the old brick farmhouse I lived in outside of Cortland, NY until I was nine. I remember taking a pencil to a yellow pad and for whatever reason drawing out the floor plan of the house and thinking that was fun. I may be a nerd.


I love my new challenge coin! I haven't had a coin check yet, but I did toss it to decide what to have for dinner yesterday!

What's the process of designing these coins like? Any particular inspiration or designs that you guys want to put on future challenge coins? Or any rejected designs?


My first thought with this coin was to sort of look back to and do a newer version of the original (like: a bunch of icons), but in the end, a manhole cover just ... worked. It was the perfect mundane universal thing for the front. Then for the back, thinking in circles, the book illustration of the cistern covers came to mind, then we tried to figure out what else we could work into the frame with it. Roman had the brilliant idea to make the little cistern cover on the back look like a miniature of the front side, too. In the end, the MuchMore team brought the whole design to life!


I just started the book, and saw a reference to the Can Opener bridge in NC. I've followed the bridge's youtube page for a couple years now, and wondered if you had a favorite collision or story about the bridge?


To me it's the progression more than any one incident - like the fact that they keep trying fixes, and they keep not working. It's a strangely persistent problem. People just ignore all these signs and blinking lights!


My favorite fun fact I've learned from the podcast is small/medium/large clothing sizes not being a thing before the civil war. (from episode 226 )

What are your favorite fun facts to come from your research?


I'll tell you one that's front-of-mind just because I wrote an article about it recently: the invention of the forerunner to the modern bicycle, which was indirectly the result of a volcanic eruption. It's a weird little story


Hi! I love 99pi, it always keeps me entertained on my multi-hour-long drives up and down California. I always loved how I could look at things as they were being spoken about. However, being from another country (Malaysia), many of the topics brought up in your show would be extremely foreign and hard recognize had I never seen them in person before. So, I have a few questions:

  1. How do you use descriptive language and sound effects so well to help visualize curious objects to people who have never seen them before?

  2. Could you recommend other podcasts that are as design-focused as your show, but not America-centric?

  3. Could you please turn down the sub-bass a little on your podcasts? Blows out my speakers every time Roman laughs! (Partially kidding on this one)

Thank you again for producing one of the best podcasts I have ever listened to! I can’t wait for my order of the book to arrive.


I don't have answers for 2 or 3, but for 1: Roman describes it pretty well when asked this question, so I'll try to paraphrase, but there are basically two ways to do it - you either go simple, give people the gist of a design so they can follow the story, or you go into a lot of detail if the details are really important to the story. I get to cheat a bit because when I'm writing articles, of course, I can drop in images and videos (in the book: illustrations!) ;)


Hey just want to say that 99% Invisible is my absolute favourite podcast, especially as someone studying Product Design at the moment. My question is how do you stay motivated/inspired to keep the constant output of amazing work? Especially now considering the current circumstances of working from home.


Funny thing for me is: I did this for a long time before joining the show. I spent 8 years working from home and from coffee shops on various web publications, so it feels familiar.

Of course, on a personal level, it's still a bit depressing not to have normal everyday interactions or be able to safely fly and visit family or friends in other cities, but work-wise, it's not too tricky. We're on slack a lot!


What do you think is your most underrated episode or subject matter? Already have my preorder challenge coin BTW!


I mean, just something fresh in mind, but I thought this silly little story about a county seal might have gained more traction than it did. As for episodes: I feel like every episode is appreciated by different people - almost every time someone will respond with something like 'this is my favorite episode ever!' which is just great.


What is one place you never expected to find yourself when researching a story or following someone up for an interview?

Also, want to thank you all for accompanying me the past couple years on my long car rides, grueling layovers, and Amtrack expeditions. Very excited for the book!


Hmmm ... maybe up on top of this hill checking out airmail arrows


You've had at least one episode on universal design, i.e., design that considers the needs of differently-abled people, but it didn't touch how much design favors right-handed people. Vending machines, cameras, phones, subway turnstiles, scissors, keyboards, etc. are all designed for right-handed people.

Maybe I've missed an episode that touched on this, but have you considered talking about design that doesn't leave left-handed people feeling left out?


This has definitely come up from time to time - I can't speak for the whole team, but my best guess is that we haven't found the right 'story' to make it work yet - like as a topic it's definitely of interest, but to make an episode it needs characters, a focus, an arc. If nothing else, though, it would make for a good mini-story I think - that's a format that lends itself to talking about ideas rather than characters. If you have a specific story/character you think could anchor a piece, though, suggest away and I'll drop it in our ideas channel!


What possessed you to use the phrase “relic of the 1900s” in your latest episode and cause me to have an existential crisis about how old I am?


So I wasn't in on the edits for that one, but ... I can confirm that I am a relic of the 1900s too :S


I'm a student journalist and a huge fan of the show so I have to ask -- do you ever take interns?


We haven't since Avery, I think, who started as an intern before coming on full time (many years back). Onboarding people during this pandemic is also tricky, to say the least, so I'm not sure if we have any near-future plans to.


I'll take the bait: who is your favorite producer?


I see someone caught Vivian's post on twitter :D


Favorite building? Either as an architectural design, or as a place that has played a significant part of the events of life that have gone on there.

Been a fan for many years, proud owner of 3 Radiotopia challenge coins and a fierce reader of plaques :)


That's so hard, but I'm a big fan of the Midtown Exchange in Minneapolis - a great example of adaptive reuse. It was actually part of a story I pitched Roman before I even joined the show, and eventually wrote a 99pi article about.


My 11 year old daughter is obsessed with your podcast so of course we bought the book. Any advice for the best way of using the book to help her discover new things about our town?


Wow, good question. I think the first two chapters are good for general orienting toward looking around and being aware of things that you're meant to notice (but don't think about) or generally overlook - they sort of lay out the framework with concrete examples and lots of illustrations, setting the stage for the rest of the book. As for specific entries: traffic lights, lane dividers, a whole section on synanthropes (animals that live in cities) are good potentially.


What was your first podcast? How did you get started?


Well that's an easy one for me: I got started when Roman hired me ;)


I always come to AMAs hours after they have finished, but this is the first one I’m truly sorry to have missed. 99pi is honestly my favorite podcast, and I listen to a bunch!

In the small chance that /u/KurtKohlstedt or /u/romanmars show back up, I wanted to ask which of your episodes you feel would be a great supplement to a high school English teacher’s lesson?

Thanks for doing what you do!


Oooh, I love these kinds of questions. Interrobang could be fun. The Universal Page is another good one. Froebel's Gifts is me being biased because it's not really about English but it is about education!


Do you feel like you have always had a unique way of looking at the world around you, or were there experiences in your past that opened your eyes to seeing the visible but not obvious things around us?


If one thing changed the way I look at the world more than anything else, it was taking drawing classes in college - you start literally seeing the world differently, its shades and shapes. It was transformative.


What has been the most Interesting episode you've been apart of?


Unpleasant Design, then later: Froebel's Gifts was just great. I had been thinking about it for a long time, then we did a version of it live on the Radiotopia East Coast tour, then we made it into an episode! It's still amazing to me that I had never learned anything about Froebel's work or the influence of kindergarten when I was in architecture school.


Something I've wondered since travelling around Asia is how different the use of Bikes/Motorbikes are there, and then contrasting that to the western world when it was at a similar stage of development (at least on a GDP/capita basis). From a design perspective, how different do you think major western cities like New York would be if the bicycle were ubiquitous 100 years earlier?


It's hard to even imagine, but NYC also got really close to closing down more streets for pedestrians and cyclists just half a century ago (we talk about that in the book, too!).

I'm just glad at least for how pedestrian-friendly the city is for the most part - if I lived and cycled there I'm sure I'd be frustrated, but when I travel there I just love walking around and taking the trains.


I absolutely love this podcast. My question if I haven't missed you: how are you able to make things that sound so mundane or boring so interesting? Every time I see a topic and think...ehhh...maybe I can skip this one, it ends up being so fascinating.

My personal favorite episode is the one about the Tel Aviv bus station. It really stuck with me.


For me, I'd say: I'm a nerd - I geek out about stuff - so sharing that enthusiasm is easy. For articles, I can just nerd around for a few paragraphs, but for episodes the other ingredient is characters - one of Emmett's stories comes to mind, where he had an idea, found really good character and ran with it. Welcome to Jurassic Art


Roman, love the pod. How do you think design will change because of COVID?


We actually went into this quite a bit with Lisa Gray in a Houston Chronicle interview last week!


Hey Roman and Kurt--Love the show and can't wait to read the book! What's a smell that you associate with your childhood?


Coincidentally: a book! More specifically, a book about the rainbow serpent. It was an Australian children's book (we lived there for a while when I was very young). I found it and cracked it open decades later and it was like being transported through time. Other than that: leaves - giant leaf piles in our yard in Cortland, New York.


I'm late to the game, so I hope that maybe this will get caught later. Greetings from Canada! I absolutely adore your podcast.

I've mentioned it in a Facebook post before, and I know this might be early to ask since you just now released your book, but do you have any plans to publish another one? Maybe a children's book?

I'd love to explore the concept of design with my daughter as she grows up. If you have any book you'd recommend (either for young children, and above), please let me know!


We've definitely thought and talked about it, but my guess is we'll take a bit of a breather and wait until things settle a bit before talking more on this - we're both (Roman in particular) just so swamped right now!

It's hard to think very far out ahead ;)


Is sports in general a favorite topic of yours to cover when it comes to dissecting the design aspect of it? (Indirectly nudging you to cover more sports content as a sports fan myself)


It really depends on the producer - we all have different interests which makes for some good variety! Emmett, I would wager, is the most into sports - Chris is working on a sports-related story right now I believe as well. I am not much of a sports fan, but did an episode coda a while back about soccer balls :)


I’m in Berlin, Germany, and many of my friends listen to 99pi because it’s not just centered on the US. What’s a design you found somewhere in the world where you thought it was genius and couldn’t believe it’s not universal?


Oh mein Freund, ich hab was fuer dich - etwas das ich eigentlich erst in Deutschland begegen habe! Diese wundervolle Fenster - this and more can be found in this episode too ;)


Have you ever researched the ISO? Seems like its make a great episode.


We've definitely bumped into the ISO in articles and episodes, might even be a reference in the book - Icon For Access involved ISO for sure! Probably nothing with ISO as the sole focus, though.


Hey Kurt and Roman, you guys have my favorite podcast by far (though What Trump Can Teach Us About Con Law is up there as well). What is one aspect of your daily life that you feel still needs some attention from a design perspective? I'm thinking something that is necessary to deal with, but always feels lacking.


I wrote an article about this group a while back that made parking spots for Bird and other electric scooters by basically spray-painting (with a stencil) them onto open areas. At least around here, scooters just end up in the middle of sidewalks, creating accessibility issues. They need dedicated parking!


Why has 99% Invisible never done a show on sound design and what goes into designing a sound? Or did I miss it?

- That animals in documentaries are usually sound designed

- The Wilhelm Scream

- Hitchcock on what it sounds like to stab a human

- The sound design of Horror Movies and why it does what it does to our psyche.


We've done some of these! Sounds Natural is about the first topic you mentioned, and there's also The Sound of Sports and Reverb! You might want to check out our whole sound-related category!


Love the podcast, been listening for years, and I just gotta say when are we spacecraft designers going to get an episode or two? Seriously, hit me up sometime.


I know Roman had an idea a while back for something ... I can't remember what exactly ... but definitely space-related design ... not sure why it got shelved. If you've got an idea, though, drop a line at !


Do you know whether the rules that determine how wide streets need to be or what type of traffic signals must be installed that are based on the density of the housing or commercial zoning in those areas?


Short answer: it varies! A lot of these are municipality-level decisions with different sets of rules.


What are your thoughts on "form follows function"?

What was the most memorable situation where this principle was not applied?
What was the reason for it?


So that term is pretty loaded and its history is pretty interesting. People think of it as meaning 'things should be boxy and devoid of ornament' - like, it reflects Modernism. But the architect who coined it still used a lot of decor, so it didn't mean the same thing to him. One can also ask: is part of the function of a building (particularly a civic or institutional one) to be beautiful? Is that an example of form following function?


Which episode of 99PI do you think is the funniest?


Whomst Among Us Has Let The Dogs Out is pretty entertaining. Let's see ... Interrobang is pretty irreverent. Or maybe another piece by Joe that we featured before he was even on staff: The Mojave Phone Booth!


I loved episode #350 "The Roman Mars Mazda Virus" since it finally answered why I can't listen to your podcast since buying a Nissan. I know you provided a link to a Mazda (and Nissan) safe version but I can't figure out how to access it with Apple's Podcast app. Is there a way?


I'm honestly not sure - all I know of is this feed link!


Have you ever been to Philadelphia? What’s your favorite building or part of the city?


City Hall by a landslide - it's even in my pinned tweet!

Last I checked it was also still the tallest masonry building in the world.


Are you a billionaire ?


I ... am not ... even close. I'll go out on a limb and say Roman isn't either, but he can correct me if I'm wrong.


I've been listening for such a long time, big thanks for all the hard work.

Do you ever feel like you're running out of stories?

There's been so many other podcasts in the last decade that were great to start with but either had to change direction to keep up with the content or just lost the magic somehow. You guys always manage to keep it fresh and I look forward to hearing a bunch more!


Just the opposite - my story list grows faster than I can keep up with, in part due to fan-submitted ideas. We have been trying to come up with better systems for organizing and storing episode ideas, too, so they don't get lost in the shuffle - sometimes we'll talk about something, then it'll just get shelved for a while until someone remembers or we bump into a new facet that fits the story and jogs our memory (happens to me a lot).


Hi, Roman and Kurt! I bought two copies of the book the day I heard about it. I am presently refreshing the tracking page constantly. The challenge coin was really cool! It’s my first one, I’ll have to get more! What do all the marks on it mean?

What’s your favorite city to visit? Why?


So front of coin you have pick points (used to insert metal rods to lift covers) and an anti-slip grid, then of course text around the edges, a common manhole cover trick.

Back of coin there's a cistern circle (you'll know it when you see it in the book!), symbols that are drawn (har har) from the first big illustration in the book on utility markings, and a few people walking over the cistern cover (which incidentally if you look closely is like a small version of the front side of the coin) ;)


Are you able to share any interesting feature related to the acoustic design of a city? I'm interested in urban planning and maps, but have taken courses in signal processing back in uni, and now found myself thinking about ways to explore or relate to the built environment (and natural environment) through sound. Sound is very much invisible - :) - so I thought you would definitely have a quirky or thoughtful take on this. Thank you very much!


Sound design in cities is ... tricky. We have a section of the book about street canyons and how they impact wind and temperature. I've also written a bit about buildings that make bad sounds. But acoustic design at an urban scale, I'm not even sure how one would approach that (maybe at the level of municipal legislation re:materials?).


Your episode about UTBAPHs is one of my all-time favorites.

Are there any other iconic brand-architectures that have taken a second life that you’ve never had a chance to report?


Ohhhh yes. I did a pretty short roundup of these a while back. On a bigger scale: Sears buildings


Why is your chuckle so soothing, Roman?


It is a mystery to us all :o


If I had to share just 1 episode to a friend to get them hooked on the show, which should I send? Sorry, no “all of them” or “it depends”.


The House that Came in the Mail. I also do roundups each year on twitter of shows recommended by interest and recently collected a page of staff favorites!


What is the very best cheese?


It was the first question, and I've been thinking on this for a day and still have no answer. Or too many answers‽


Hey for anyone who has bought or looked through the book, is it a compilation of podcast info or does it have unique content?


It is definitely not a podcast compilation - that was the last thing we wanted to make it. Most of the stories are things that were never on the show. Some were mentioned on the show, like in codas, then fleshed out for the book. Some were rewritten for the book. But aside from an occasional good quote or phrase or joke, it was all written from scratch whether or not a given essay drew on a particular episode. In some cases, too, there's something like the reversal of the Chicago river, rewritten and with a new introduction (about how it turns green once a year) and conclusion (about how it's starting to re-reverse, and its future is uncertain). So you may encounter stories, characters, ideas, etc... from the show, but it shouldn't feel like a pile of transcripts.

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