The enormous 250-room Vanderbilt mansion conceals hidden doors and secret passageways.

Mountain where Jesus was first tempted by the Devil.

The largest Art Nouveau complex in the world is a Barcelona hospital with a 600-year-long history.

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

A poetic monument to the Scottish Parliament.

This charming old building's loose connection with the Scottish Reformer is what saved it from demolition after it split apart.

This stately monument has been wearing a traffic cone hat for decades much to the delight of the locals.

The most loyal of little dogs, or a Victorian era publicity stunt?

Overlooked by many, the two famous Scottish warriors guard the main gate of Edinburgh Castle.

17th century streets hidden under Edinburgh were once a breeding ground for the black death.

Ruined 11th century abbey built by King David I in Edinburgh, Scotland.

Thirteen pastel palaces in downtown Charleston add a gorgeous splash of color to the city.

Once the most flame resistant building in the country, the South Carolina Historical Society building was almost burnt down in a fire.

Oldest unrestored plantation house in America that is open to the public.

South Carolina's last remaining slavery auction house is now a museum devoted to its own tragic history.

This quirky UFO-shaped curiosity is often mistaken for the airport’s control tower.

An historic and oft-filmed spot for musclebound iron pumpers on the Pacific coast.

These two monoliths have stood at the entrance to the neighborhood since the days it was called "Hollywoodland."

Outposts of this restaurant chain were shaped like jaunty chapeaus.

The world's oldest hologram gallery and the labyrinthine laser laboratory of a holography pioneer.

Two creeks flow out of either end of this canyon in opposite directions.

Air Force Academy Chapel made of 100 identical tetrahedrons works to inspire those of all religions.

Thanks to a quirk of elevation this gift shop produces magic doughnuts that are found nowhere else on Earth.

When ecosystems collide in the arid Southwest.