One of the oldest and largest castles in the world.

A 1,500-year-old ghost settlement is slowly fading away.

One of the world's largest shopping malls covers an area of 15 million square feet—and it's still set to grow.

This 17th-century structure is a beautiful testimony to traditional Persian architecture

One of the largest and oldest caravansaries in Persia.

This remote fort on the Yukon River is a vestige of the wild Alaska gold rush.

This vacant church in the Financial District was once the heart of New York's first Syrian immigrant community.

These World War I shooting range tunnels are now haunted halls of underground graffiti accessed through the roots of a tree.

This Florida arena, once host to "the fastest game in the world," has sat empty for 25 years.

This railroad tunnel was once the longest in Massachusetts.

A mysterious, abandoned building rotting on the Brooklyn waterfront.

If you've ever wanted to learn about the history of Asian fish balls, this Taiwanese museum has you covered.

A 19th-century fortress and collection of artifacts offer a tour of Saudi history.

An annual two-week festival near the city of Riyadh when Saudis let their hair down.

This mesmerizing, colorful structure looks like a tent made from stained glass.

An archaeological site believed to be the burial place of the "mother of us all."

A huge stone pyramid built for fun.

Cockatoo Island is a Heritage-listed island in the middle of Sydney Harbour.

This shrine to film's most iconic wasteland wanderer is located in the very outback where the movies were shot.

Clusters of huge boulders in the Australian Outback.

An ancient rock engraving shows Aboriginals used their advanced knowledge of the stars to hunt and gather.

Visitors can swim with vicious predators in Crocosaurus Cove's plastic daredevil enclosure.

This pair of Australian "waterfalls" appear to be falling straight across the land.

Woven tree art gives this towering Australian woodland a touch of mystical whimsy.