A modern mechanical planetary system, part of a 10,000 year clock.

An artsy hidden staircase leads to breathtaking views of San Francisco.

An "anarchical" no man's land, complete with garbage sculptures and a hobo-run "Landfillian Library."

A porcelain company's former dumping ground, completely covered in pieces of collectible ceramics.

Since 1973, this block has been home to the most concentrated collection of murals in San Francisco.

A local dialect born in the late 19th century is only spoken in this isolated California valley.

A poignant memorial to a young boy whose death spurred a dramatic increase in organ donations in Italy—dubbed the "Nicholas Effect."

This whimsical seashell-shaped place of worship was designed to blend into its surroundings.

The southernmost outpost of the Russian Empire in colonial America.

An ever-growing literary collection housed in the apartment where the Russian author penned his final novel.

Perhaps the tiniest sculpture in Saint Petersburg is a little bronze finch inspired by a song.

This whimsical campus lawn is dotted with large sculpted numbers and hidden mathematical formulas.

Funded by John D. Rockefeller, this is one of the earliest, and most beautiful, shopping arcades in America.

This grinning pup statue is all that's left of what was once a ubiquitous Bay Area diner chain.

This eatery transports diners to a place that no longer exists: East Germany.

The neighborhood church casts a breast-shaped shadow that locals have come to call the “two o’clock titty.”

Depicting scenes of everyday life - and specific individuals - in Great Depression era San Francisco.

The second building of its name to occupy this location might be the finest flatiron building in San Francisco.

An elaborate gift from Claus Spreckels is now a piece of San Francisco history.

The key to turning shifting dunes into the green oasis of Golden Gate Park.

A library built during San Francisco's pioneer times is a student's retreat, bibliophile's sanctuary, and chess player's delight.

A historic hotel that made a cameo in Hitchcock's classic film has no intention of letting guests forget its fame.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

Relics of the 1894 Midwinter Exposition continue to delight visitors today.