Places CL Tee Wants to Go

Mysterious Spanish catacombs of unknown origins.

Partially collapsed lava tube and cave system complete with concert hall, underground pond, and unique albino crabs.

A charming Spanish village sits atop this natural limestone overpass.

The abandoned ruins of a beautiful medieval castle just outside Barcelona.

Stunning Roman aqueduct used for 1900 years and still standing.

The earliest known map to show America, discovered by accident at a Paris bookshop.

Considered the birthplace of the Copper Age and Bronze Age, the river is tinted red from 5,000 years of mining.

A Franco-era dam flooded (almost) everyone out of this centuries-old Aragonese town.

Cliffside houses provide a spectacular view from their perch above the valley.

A completely underwater art museum sends a stark message about humans' impact on the environment.

An isolated village literally built into the crevices and rock formations of a mountain.

A Spanish town built into the cliffs.

This awesome Spanish castle is so fantastical it was actually used on Game of Thrones.

The world's largest wooden structure.

Village situated on a narrow volcanic escarpment.

The morbid items in this small and hidden museum are not for the weak stomached.

This Navarrese cave's history of witchcraft and pagan ritual is not just embraced, but recreated each year.

One of Europe's largest supercomputers is housed inside of a disused chapel.

Barcelona's historic 19th-century sewers, whose foundations were laid in medieval times, are open to the public for exploring.

These secluded and abandoned anti-aircraft defenses have become one the most scenic viewpoints in Barcelona.

A beautiful but toxic fountain of mercury.

Turntable anonymously received orphans, alms, and groceries.

A lush indoor jungle fills this bustling Madrid transportation hub.

The 2,000-year-old Roman columns are hidden within Barcelona's Gothic Quarter.