Guide to San Francisco's "secret" public parks in commercials spaces

In San Francisco, there are 21 "secret" public parks, atriums, and beautiful rooftops hidden behind unmarked doors or accessible through guarded elevators. Commercial developers are legally required to build these Privately Owned Public Open Spaces (POPOS) but they'd mostly prefer people not use them. Matthew Lew, a hypertalented design intern in my group at Medium, created a guide to these delightful POPOS.

The 21 Secret Parks of San Francisco