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

Tiki luxury on Nob Hill.

San Francisco's newly reopened hands-on science museum.

Staircase winds down the side of Telegraph Hill through gardens, wild parrots flying overhead.

The seawater playground of gilded-era San Francisco burned to the ground in 1966.

A walk-in working camera obscura produces 360-degree live images of the San Francisco coast.

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

Olfactory delights in San Francisco's Botanical Gardens.

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

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

A winding path built in secret on the edge of the continent.

A huge musical instrument played by the ocean.

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

A grand New York post office that is home to mailman Santas, scraps of postal history, and a pneumatic mail system.

This Manhattan skyscraper is a reminder of the brief but glorious age of urban air taxis.

The longest continuous underwater road in North America was built at the insistence of Franklin Roosevelt.

You must take the A train... to the last active cemetery in Manhattan.

The former sign of this immortal music venue is just that--undying.

This subterranean oyster house has been the pearl of Grand Central Station since 1913.

A remnant from the golden age of aviation still in use today, Pan Am's Clipper service took off from this Art Deco gem.

Long-forgotten artifacts give incredible insight into New York's most glamorous hotel.

The most confusing clock in New York.

This historic address is home to the beloved ball and is an almost totally empty building among the most expensive real estate in the world.

The New York hotel where tragic visionary Nikola Tesla spent his final hours, destitute and alone but for the pigeons.