The Cable Car Barn and Museum is just that -- a combination of a working cable car hub as well as a museum of cable car history.
The museum is free and a walk through -- for adults or children -- provides a fascinating look at the sheaves and mechanism that actually run the cable system under San Francisco streets. You feel a part of the machine when you're there, with the sounds of the sheaves and both a surface and below-ground viewing area of the cable structure.
The museum displays artifacts, photos and historical information. There's also a video showing the genesis of the cable car system. Be sure to sit close to the screen or the sounds of the cable car barn may drown out the audio.
The museum is accessible via the Powell-Hyde and Powell-Mason cable car lines. See the Cable Car Route Map for detailed information.
To learn more about San Francisco's historic streetcars -- running on the Embarcadero's F-Line -- visit the San Francisco Railway Museum at 77 Steuart, near the San Francisco Ferry Building.