London's smallest police station is barely the size of a phone booth.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

An ethereal glowing blue ocean cave in Croatia.

This beautiful natural train tunnel is said to grant the wishes of visiting lovebirds.

A spectacular cave and a beguiling lake.

Space-age monument to an early 20th-century uprising.

Monasteries on rock pillars, once accessible only by frayed ropes.

An abandoned saucer-shaped monument in the Bulgarian mountains.

This ancient village and its adjoining cemetery have a beautiful history of death and remembrance.

A castle perched precariously over the Crimean Sea.

Turnip-shaped island just off the Michigan shore in Lake Huron.

Home to the infamous "Typhoid Mary" and the worst loss of life in New York's history prior to September 11, 2001.

100 massive sculptures in the Hudson River Valley.

Collapsing castle on the Hudson river was once the storage site of military surplus business.

This unique structure in suburban Austin is made up entirely of other people's castaways, and constantly changing.

A National Historic Landmark with a scenic clock tower and park filled with deer and peacocks, plus a military museum.

An emerald-green grotto just a short trip from Austin.

Marking the spot where a conquistador gave up his search for the fabled Seven Cities of Gold.

Hauntingly beautiful totem poles left by the Haida.

A gargantuan crystal kingdom.

A waterfall 600 ft. inside a mountain, once the bane of gold miners, is now a spectacle of nature.

The first declared National Monument in the United States.

Fossils, railroads, and waterfalls!

Few other hotels can rival the grandeur of the Castle in the Rockies.