A cedar barrel sauna at Crane Cove Park is one node in a citywide wave of public saunas that has landed address by address across five neighborhoods — cleared in part by the 2024 repeal of the police oversight that once governed bathhouse permits.

At Crane Cove Park, 701 Illinois St., a four-person cedar barrel sauna sits a few steps from the bay, held at 190 degrees, with a plunge into the 53-degree water for anyone willing and cold showers for everyone else. It opened last April as a sideline to Dogpatch Paddle & Kayak's boat rentals — $25 an hour, or $75 a month for unlimited use, per the San Francisco Standard's roundup of Bay Area saunas (external source, opens in a new tab). Owner Adam Zolot figured he and a few friends would use it. Instead it drew regulars, most of them from the surrounding blocks, he told the San Francisco Chronicle.

The corner isn't alone on the map. The city's count of saunas open to the public has climbed past a dozen, nearly all of them recent arrivals, the Chronicle reported this month — heat-and-cold rooms that have settled, address by address, into neighborhoods that had almost none a few years ago.

The blocks tell it plainer than the trend does. In the Tenderloin, the reopened Onsen bathhouse holds 466 Eddy St. — 3,200 square feet with a redwood sauna, a cold-plunge shower and a 15-person pool kept at 104 degrees, per the Standard (external source, opens in a new tab). In Lower Nob Hill, Alchemy Springs installed what it bills as the country's largest freestanding sauna, a 40-person ring, behind 939 Post St. Across the water, Fjord soft-launched a wood-fired room atop a floating wave attenuator at 2310 Marinship Way in Sausalito, and Good Hot runs five hand-built rooms behind a scrapyard at Point San Pablo in Richmond.

Some of what cleared the way came from City Hall. A section of the police code once handed bathhouse permitting to the SFPD and required operators to keep a daily register of patrons; Supervisor Rafael Mandelman spent four years unwinding the AIDS-era rulebook — a 2020 health-code measure, a 2022 zoning change — before the board repealed the police-code article in December 2024 (external source, opens in a new tab). Castro Baths, whose owner Joel Aguero called the police role a significant blocker, is among the projects that repeal clears (external source, opens in a new tab).

These storefronts don't sit on placid blocks. On the Tenderloin streets around Onsen's 104-degree pool, city records show 42 eviction notices filed in the past 90 days and 822 requests to 311 in a single week — recent filings on the 800 block of O'Farrell and the Polk Street corridor among them. That's the contrast a soaking pool now shares an address with: rooms that were scarce a few years back, opening in neighborhoods still logging the older kind of heat. Walk past Eddy or Illinois tomorrow and the new sign is the thing you'd notice — a door that wasn't a door before.