A micro-communist utopia in Spain with no police, no mortgages and full employment.

Spain's unique Mosque-Cathedral has been a place of worship for both Muslims and Christians throughout its history.

A dangerous narrow-gauge railroad once traced a route through this striking canyon.

One of the largest Buddhist stupas in North America is built of concrete designed to last 1,000 years.

This once-popular otherworldly landscape was formed by one of the largest volcanic eruptions in history.

This tea house was a hand-built gift from Boulder's sister city in Tajikstan.

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

An artifact taken from one of America's shortest wars.

A museum dedicated to linguistics, from how babies learn to talk to endangered and extinct languages.

The industrial architecture honors the laborers who brought the Exposition Universelle of 1900 to life.

This Parisian gem is one of the most incredible ethnographic museums in the world.

This nearly abandoned "company town" is a ghost of Puerto Rico's once-lucrative sugar industry.