Grotto replete with mystical designs laid out in glued shell mosaics.

The United States's largest hand-dug well is topped with a state-of-the-art museum.

Some locals believe the fabled lost gold of General Yamashida is hiding somewhere beneath the city.

No one knows the origins of the mysterious stone ruins discovered on a hillside in Halifax.

Eastern Canada's ocean playground.

Hunt for buried treasure in Nova Scotia.

Steadily reminding Czechia of its past.

A giant portrait of an ancient king looms over the river.

This 14th century castle withstood years of battle but is now sliding off the hills into the Danube.

Costumed elves and mountain bikers co-exist peacefully at this abandoned Christmas-themed adventure park.

A stunning 18th-century site where pilgrims ascend by a series of punishing stairs only to return via funicular.

Local lore says the devil built this beautiful medieval bridge to help a fleeing bandit.

A submerged village appears when dam levels drop.

This Costa Rican topiary park is a surreal garden of unearthly delights.

An eight-sided home built during a brief octagon craze in the 1850s.

The abandoned tuberculosis sanatorium is said to be one of the most haunted places in Canada.

Now abandoned, the first public health hospital in the U.S. saw more than one million immigrants from around the world.

Two 2,500-year-old Phoenician boats found on the coast of Spain, giving incredible insight into the ancient maritime traders.

Half-hidden by grassy slopes, this striking Spanish colonial fort is now a museum of underwater archaeology.

This delicate museum is devoted to the art and industry that once supported Cape Cod's oldest town.

The sand is such a bright white that on sunny days you practically need sunglasses to look at the ground.

This massive water spout has been luring visitors for hundreds of years, some to their death.

These sea cliffs are an epic natural wonder.

The historic tower houses of this nearly abandoned Greek town have been compared to the spikes on an iguana's back.