Swimming competitions were indeed a regular attraction at Sutro Baths, sometimes drawing upwards of 20,000 spectators.

But the bleachers were also filled by a dizzying array of entertainments that included band concerts, high-diving exhibitions, tug-of-war contests, vaudeville performers, operatic singers, breath holding contests, boxing matches, animal acts, underwater escape artists, re-creations of shipwrecks and rescues, and May Day exhibitions with thousands of kids participating.

You got a lot for a 10-cent admission in the 1890s.

Good views of Sutro Baths, now gone.

[Also, check out some then and now scenes from the film. -tterrace.]

Were competitions held there? I can't understand the quantity of bleachers. Surely there wouldn't be that many people there just to watch a bunch of other people splash around.

Actually, the six saltwater pools in Sutro Baths were heated to a variety of temperatures, offering bathers ample options for seawater soaking. Boilers in the powerhouse could warm ocean water up to 98 degrees. Generally, the four small pools visible in this photo were heated from warm to cool as they marched away from the photographer.

Only the water in the largest pool (barely visible at upper right) came directly from the unheated ocean. A "dare ya" challenge among kids involved soaking in the hottest pool then immediately jumping into the frigid Pacific-temperature pool.

BTW, there's a great new book about the Baths titled "Sutro's Glass Palace: The Story of Sutro Baths" containing a wealth of historic photos, drawings, and technical information about the now-vanished landmark: http://holeintheheadpress.com/sutro.html (Disclosure: I'm the author.)

The photo made me want to know more. Turned up this site with tons of great photos of the baths.

Was diving off the top platform at Sutro Baths, practically at the roof.

The other was being assigned the helm when the freighter on which he was a deckhand transited the Panama Canal.

The Sutro Baths were part of an area just above the Cliff House (which Shorpy has also featured great photos of here) and were located near the area where a scene from the movie "Harold & Maude" was filmed. Fans may remember the scene where Harold's uncle tries to talk him into joining the army and Maude is a "war protester" who meets her demise on the rocks below.

Pacific Ocean water is what they're swimming (er, standing) in, which only hits a high of 60°F, in September. The western side of San Francisco is never-ever warm. Ever. In addition to the ocean current rotating clockwise down from Alaska, off the coast is the continental shelf that drops many thousands of feet, from which an upwelling of extremely frigid water from the black depths maintains the impossibility of ever seeing the sun on the beaches of San Francisco, let alone feeling compelled to get in the surf and "cool off." That, and the San Francisco Bay is fed by melted snow from the Sierra Nevada, which flows out through the Golden Gate, to the immediate north of Sutro Baths -- just in case. I'm cold just thinking about it. I'm going to go make a cup of tea.