October 17, 2010. Underneath the junction of Washington and Mason Streets, San Francisco. If you head downstairs at the San Francisco Cable Car Museum, you can peer through the glass at the cables in action, as they are routed down through the city.
This wasn't an easy shot to take. I was pressed up against the window trying to block reflections, cranked the camera to ISO 1600, f2.8, and had to hold still for 0.3 seconds. This may be an extremely cool place to explore / tour, without guardrails and glass in the way. Probably a good way to lose limbs too if you're not careful.
More info on Wikipedia and at the San Francisco Cable Car Museum website.