The Sutro Baths were luxurious swimming pools on the San Francisco seafront, in an almost all glass building, built in the 1890s. Complete with salt and freshwater pools, slides, and 30 swinging rings, and a springboard. It was served by two rail lines, one of these being the Sutro Railroad, another creation of Adolph Sutro, a famous engineer and industrialist and mayor of San Francisco! In the 1900s the facility fell into disrepair and it burned down in 1966. Today only ruins remain, including the pool basins, a settling pool, and tunnels.
The tunnels are approximately at N 37.780777 W 122.514105. Note that there are multiple tunnels, the main walkable tunnel that is easy to spot, it goes through the cliff and opens up on the other side to rocky views of the sea. You can't continue, but can see the view. Inside the tunnel there are holes that lead to sea caves and cracks. I couldn't tell if these were there in the beginning, or if the rock has eroded since building the tunnels.
There's also a lower tunnel that is usually flooded. Apparently the lower tunnel was used to pump seawater during low tides to slowly replace the pool water; at high tide the water would naturally flow to the pools and replenish them within one hour. It doesn't seem to be easily accessible today, or at least one would have to be ready to use rubber bootss.
While most of the ruins are at the seashore, if you walk to the observation area above the cliffs you will find more ruins, this is recommend for the views! From here you can also see (closed) stairs that lead down to an area above the lower tunnel. And from the observation area you can find further steps that lead to the Sutro Baths Trail and the Coastal Trail through the Golden Gate Recreation Area's beautiful park. Much recommended as well.
The entire area is dangerous, please be careful and do not fall from the cliffs or to the water. Don't go to closed areas.
More information about the Sutro Baths can be found here and here and here, in the Wikipedia article, or in the book "Sutro's Glass Palace - The Story of Sutro Baths" (Amazon link). More information about Adolph Sutro can be found in his Wikipedia article. Another creation of Sutro is by the way the Sutro Tunnel, a flood control tunnel in Nevada.
The Sutro Baths ruins, main area:
In their time, the baths looked like this (picture source is from Wikipedia, both pictures are postcards and in public domain, the first one is by W. C. Billington, the other one by unknown. What wonderful swimming places these have been!
The main tunnel (see also the opening photo above):
The lower tunnel:
Views from the observation area:
Coastal Trail views:
Other San Francisco views:
This article has also been published at TGR. Read more urban exploration stories from theurbanexplorer.net, and other underground stories from planetcaver.net. Read the full Planetskier series at planetskier.net, or all blog articles from Blogspot or TGR. Photos and text (c) 2022 by Jari Arkko. The historic photos are in the public domain, and from Wikipedia. The last photo is by Paul Wouters. All rights reserved.