This residential door allows San Francisco muggles a glimpse at the wizarding world.

Europe's official "zero-level," the equator of elevation.

The sophisticated hydraulic system of the Nazca civilization.

The United States's largest hand-dug well is topped with a state-of-the-art museum.

This enormous spiral sculpture looks strangely out of place on the edge of a housing development.

Double spiral staircases are not unheard of, but they are very rare.

A whimsical tower with a spiral staircase, inspired by the Space Age and the Möbius strip.

Must form and function forever remain at odds? Not if the Florida Department of Transportation has its way.

This high-design church is made up of two dizzying spirals meant to evoke the weaving together of marriage.

A lavish 16th-century mansion filled with spectacular staircases, fantastic frescoes, and gorgeous gardens.

An earthwork sculpture built by Robert Smithson in the Great Salt Lake only reemerges during drought.

A popular 19th-century natural landmark is now hidden within a sprawling forest.

The Dead Sea Scrolls were discovered in the ruins of this ancient monastic community.

The world's last remaining store of its kind.

Centuries later, the victims of Great Britain's greatest hysteria are finally being remembered.

This 7,000-year-old megalithic wonder covered by a Franco-era reservoir emerges in times of drought.

This Aztec structure remained hidden until the demolition of a supermarket exposed the lost temple.

The legacies of two historic Black American institutions live on in this unassuming brick building.

This Portland shop is brimming with natural wonders, local art, and handmade goods fashioned from recycled materials.

A monument to the migrants who cross the dangerous waters between North Africa and a tiny Italian island.

A neighborhood park in the city of Cáceres hides what some believe are revolutionary examples of Neanderthal cave art.

This unusual subway stop was originally a real estate office.

A modern zoetrope on the New York City subway.

This innocent-looking townhome is actually a subway exit.