Early on, housing lots in San Francisco were subdivided into plots as little as 25 feet wide -- just enough room for a parlor and a staircase.

Reported by Sarah Craig. Bay Curious is made by Olivia Allen-Price, Jessica Placzek, Paul Lancour, Ryan Levi and Suzie Racho. Additional support from Julie Caine, Ethan Lindsey, Katie McMurran and David Weir. Theme music by Pat Mesiti-Miller. Ask us a question or sign up for our newsletter at BayCurious.org. Follow Olivia Allen-Price on Twitter @oallenprice.

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