Allowing humans and fish alike to migrate from freshwater to saltwater and back again.

This ritzy Italian market is built around a statue of an unforgiven heretic who was burned for his belief in an endless universe.

A mushroom-shaped outcropping that has come to be the symbol for an entire town.

Pompeii's less famous neighbor is still revealing her secrets.

An underground paleo-Christian burial site composed of the remains of several cemeteries and Basilicas.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

This small Brazilian museum honors the work of a German biologist who studied the jungles for decades.

As one of the world's largest hydroelectric dams this plant took two countries to get built.

A series of waterfalls so massive they straddle the border of Argentina and Brazil.

The pedestrian traffic signals in Brazil's teeming metropolis light up with clues to nearby landmarks.