Home to items never before seen by the public.

During the Industrial Revolution this “Temple of Invention” was full of intricate miniature machines and gadgets.

The preamble to the U.S. Constitution written entirely from vanity license plates hangs in the Smithsonian museum.

Go take a picture with the inventor of the daguerreotype photographic process.

In 1958, an MIT fraternity pledge laid down on this bridge and instituted a new, unique unit of measurement.

"the sweltering inhabitants of Charleston and New Orleans, of Madras and Bombay and Calcutta, drink at my well . . . The pure Walden water is mingled with the sacred water of the Ganges."

Ornate and macabre headstone in one of the country's oldest cemeteries.

A century-old hotspot for jazz, frequented by everyone from Charlie Chaplin to Al Capone.

A muscular Art Deco monument represents the struggle between regulators and unbridled markets.

A much-maligned monument to teetotalism.

Faceless white figures loom over the city from the rooftop.

These subterranean storage areas hold emergency water reserves.

A shining, cold, black organ lies in San Francisco's financial district.

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

This private residence was the template for one of the most beloved television homes of all time.

Nestled in the heart of San Francisco’s bustling Financial District stands a unique homage to the Mayan and Beaux Arts.

Tiki luxury on Nob Hill.

A century and a half of research in the sciences and natural history, still going strong.

A favorite haunt of dinosaur loving children and hallucinogen loving hippies alike.

Carnivorous plants, medieval aphrodisiacs, and the largest original wood structure glass conservatory in the western hemisphere.

In the depths of Glasgow Cathedral's crypt, one pillar stands out from all others.

Overlooking the burial ground is a tower designed to prevent thieves from snatching the recently deceased.

The dance of this huge clock is a magnificent and eerie commentary on good and evil in the history of humankind.

Touching this 18th-century Scottish philosopher’s toe allegedly conjures good fortune.