This shrine commemorates the site of the first known Catholic mass in the United States.

Bronze footprints mark the path where a civil rights leader tried to march in peaceful protest before being knocked unconscious.

St. Augustine's record-setting narrow street was designed to protect against pirates.

These ruins are all that remain of what a Spanish barrack that likely housed a quarry overseer, masons, and stone cutters involved in the construction of the Castillo de San Marco.

One of the oldest, tallest, and most haunted lighthouses in America.

The United States' only educational center specializing in disease vectors and mosquitoes.

One of the largest Native American shell middens stands 30 feet tall.

These mysterious ruins are hidden amid this sleepy coastal city.

Despite being made of a seashell mortar, the crumbling remains of this historic Florida mill are still standing.

This small museum concentrates on the juicy history of orange production in Florida.

A swamp that was the site of prehistoric water burials also managed to preserve its corpses for millennia.

This Ukranian fortress is one of the best-preserved medieval castles in Europe.

There is a mouldering Jewish cemetery hidden away in the capital of Moldova.

Elaborate mansions built by Roma residents in Soroca to show their success after centuries of discrimination.

A fire once nearly devoured this gorgeous 14th-century Gothic cathedral.

This snug medieval lane is one of the narrowest streets in the world.

The European towns of Brașov and Râșnov each have proud signs reminiscent of the Hollywood sign.

Religious perseverance and cultural coexistence manifest in an architectural gem that multiple wars couldn't topple.

Croatia's towering concrete blossom grows from the site of a World War II concentration camp.

A whimsical bridge adorned with decorative dragons.

High atop a Mexican rainforest mountain, this ancient pyramid once drew pilgrims countries away.

The conquistador's former fortress is the oldest preserved colonial building in the Americas.

Monumental paintings, discovered in a Mexican cathedral in 1957, depict the deaths of some friars in Japan.

The former headquarters of a leader in the Mexican Revolution, and the site of an often-reproduced image.