Once a year, thousands of naked cyclists flood the streets of a Seattle neighborhood.

This Puget Sound military post has a long, turbulent history as a gateway to the Pacific.

The tech giant built three enormous glass orbs in Seattle so employees could work inside a rainforest greenhouse.

Though strikingly beautiful, Seattle's other railway station is now largely forgotten.

This bridge was constructed from the rubble of the infamous Bastille.

A surrealist timepiece by the artist of melting clocks.

This massive library holds what was once the largest book collection in the world.

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

The vast, legendary catacombs hold secrets much stranger than stacked bones.

This surreal statue brings a famous French novel about a supernatural cad to arresting life.

Paris' linguistic guide to the international language of, yes, love.

Down a cobblestone alleyway is a museum dedicated to Romanticism, with a secret garden.

This mountain trail inspired Nietzsche to complete his magnum opus.

The first geometric self-supporting spiral stairs in Britain are a truly beautiful sight.

The Denver airport is guarded by a 32-foot-tall sculpture of a demonic horse.

A downtown park built on top of unclaimed graves.

A rough granite monument marks the spot where Europeans first caught sight of the San Francisco Bay.

A trail weaves through the verses of a poem illustrated by stone sculptures inspired by Native American pictographs.

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

Olfactory delights in San Francisco's Botanical Gardens.

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

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

A tunnel of hardened lava along Maui’s famous Road to Hana.

Elaborately carved to showcase the glorious wealth that the age of exploration brought to the Portuguese empire.