A 300-ship graveyard, with a few still visible at low tide.

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

An impressive piece of infrastructure that seems outsized when considering it serves an island with a population of less than 300.

Despite what a Thai tourism board might want you to think, this white-sand beach is in fact located on a Scottish island.

It was an experiment to prove that glacial boulders and rocks can be used in constructions and dwelling.

This infamous prison has a store where you can buy goods crafted by incarcerated people.

An essential stop before plundering, BYO Cutlass.

Olfactory delights in San Francisco's Botanical Gardens.

A museum befitting the city responsible for supplying the majority of the world's LSD.

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

A tiny theater hidden in an alley plays a constant stream of short silent films for anyone willing to peer through the peephole.

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

This iconic fortress was once the crown jewel of Haiti's national defense.

A museum commemorating the Donora Smog, which killed 20 people in October 1948 and sparked national outrage over air pollution.

It wouldn't be long after purchasing this farm, Brown would lead his siege on Harper's Ferry.

For decades, Hungary's Communist Party insisted this gulag had never existed.

An architectural marvel that dates back to the zenith of Indian architecture.

This temple was constructed entirely by Roman soldiers.

One of the few working locomotive roundhouses in the United States.

An overlooked marble is the only surviving in-place 18th century example of the measurement that changed how we define distance.

This grave marks the final resting place of pioneer John Chapman, better known as Johnny Appleseed.

When Motown musicians came to Nashville in the 1960s they stayed at this historic record-pressing company because hotels wouldn't host them.

A labyrinthine underworld of tunnels and caverns hides beneath the city.

Nestled atop a wind-swept crag in the Scottish Highlands is a lonely memorial to a beloved hiker.