The Old Courthouse takes visitors on a captivating trip through St. Louis' timeline.

The longest escalator in the Western Hemisphere takes over three minutes to ride down.

Unconventional site where the tracks of Zurich tramcars intersect.

Once the grandest synagogue in medieval Spain, it now stands as a memorial of the 15th-century Jewish exile.

One of the few remaining ancient aqueducts described by Frontinus as 'the most solemn testimony of the Empire.'

A 16th-century Andalusian palace.

This sweet-toothed bear searching for snacks has been a symbol of Madrid for decades.

Over two centuries old and counting, Madrid's massive botanical garden contains one of Europe's only desert environments.

Madrid's romantically ornate crystal palace has been offering shelter to plants and art for over a century.

A graceful natural rock formation stands astride the point where the Gulf of California meets the Pacific Ocean.

Famously misunderstood wonder of the ancient world

An ancient Roman temple first dedicated to an emperor's wife is now a church.

The ruins of the largest gladiatorial school in Rome are largely hidden under modern streets.

Rome's semi-secret peephole vista is also a former Crusader stronghold.

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

A sculpture of the famous photograph stands on San Diego's "Greatest Generation Walk."

L. Frank Baum wrote part of the "Wizard of Oz" series in this wooden Victorian beach resort.

These unusual rooms on wheels are holdovers from the 1960s.

The Pentagon is so large that it was planned like a city, complete with internal highway infrastructure.

The romance of early commercial flight still fills this Art Deco destination.

This isn't your average roadway—it's actually a National Park and a transportation pioneer.

A former major munitions plant that has been converted into a sprawling art space.

This lovely picnic spot featuring thunderous jet landings is an aircraft spotter’s dream.

At 207 feet, one of the world's longest continuous escalators.