This is 99% invisible. I'm Roman Mars and I'm in the octagon house in San Francisco, California.

With Arie Drovelment.

So I used to work for 99% invisible and I used to live in the Bay Area and I recently came back for a visit and I wanted Roman to see this octagon shaped house in San Francisco.

I mean, had you encountered an octagon house before?

No, I mean, I must have passed this one at some point. I lived in San Francisco for eight years.

I once thought this house was some sort of standalone bit of quirky architecture, but when I left the Bay Area, I realized

this was not the only octagon house. Octagon shaped houses are absolutely everywhere.

There's a whole bevy of Octagon houses out in Long Island.

There are at least a dozen Octagon houses in upstate New York,

and if you zoom out there's one in New Bedford, Massachusetts, in Connecticut, in Kansas, in Alabama, and honestly, if you search Octagon house plus state, you will probably find one.

This Octagon house, the one out in Cal Hollow,

isn't even the only octagon house in San Francisco.

There are two others.

But it is the only one that's open to the public every other Sunday

It's lovely. That's the first thing. Yeah, can you do your magic? Can you describe it? It's powder blue. It is an octagon

It has these things that where I think are kind of the joins where each side joins, it looks like a hinge, so it looks like a giant toddler that unfold. Yes, it's very Fisher Price is like the vibe.

This octagon house was part of a bona fide trend, an 1850s architectural fad.

People believed that octagonal houses would lead to better, healthier, happier lives that were more in touch with the natural world.

And so I was like, I've got to see if there's anything to this.

I wanted to get into one of these utopian octagon houses to see what it was all about.

All right, well welcome to the octagon house.

The technical name for this octagon house is the McElroy house because a family named

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