San Francisco's oldest surviving monument and meeting place for 1906 survivors.

Not merely a museum – but a whirring powerhouse that offers a subterranean peek into the heart and soul of cable car operations.

Iconic Los Angeles residence famous for its 19 statues of Michelangelo's David.

Historic funicular railway, believed to be the shortest railroad in the world.

Panorama exhibition hall in old silent theater with a beautiful backyard garden.

This Arizona observatory is famous for investigations into Martian life, and as the place humans first spotted Pluto.

A small "palace" and museum made of, and devoted entirely, to salt.

Park filled with machinery that drove the southern agriculture and oil industries forward.