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

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

A collection of 20th-century automata, penny arcade games, and musical contraptions.

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

Tiki luxury on Nob Hill.

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.

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

France's most famous cemetery, with some of its most curious tombs.

An intricate network of underground tombs carved into volcanic rock.

This "volcanic all-day restaurant" is right on the beach.

The oldest standing Byzantine church in Athens is tucked within a monastery in the middle of an upscale shopping district.

This gem is often wrongly overshadowed by the larger, newer Metropolis church in Athens.

Where commuters walk through remnants of an ancient Greek necropolis.

Legend says this sacred tree was a gift from goddess Athena.

The Cycladic architecture makes this Athens neighborhood feel like an island paradise hidden in the shadow of the Acropolis.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

A 2,000-year-old computer demonstrates remarkable engineering and astronomical precision.

Beneath the southern end of the Golden Gate Bridge is the “Gibraltar of the West Coast,” a fort built to protect the San Francisco Bay from naval attack.

This lighthouse has been guiding shipping into the Golden Gate since before the American Civil War.

Ride on a fully-restored Nike nuclear-tipped missile elevator from the Cold War.

Concrete strongholds stand guard over the Golden Gate.

Dive bar built out of the remains of a whaling ship.

Take shelter from Hawai'i's tropical heat under the massive canopy of largest Banyan tree on the island.