This fancifully decorated Victorian home in New York’s Hudson Valley is the only known fully domed octagonal residence in the United States.

An original apothecary from 1792.

A series of caves, tunnels, and wells filled with fascinating figures and symbols.

Ottoman-era houses lovingly preserved.

Mosaics, storks, and brothels—this ancient city has it all.

Designed as a labyrinth, this subterranean prison was crafted without bars or doors.

The land is full of geologic eye candy, such as otherworldly spires, mushroom-shaped hoodoos, and prehistoric fossils.

The largest treasure hoard in Europe is contained in a castle that was bombed out during World War II.

The largest puppetry museum in the United States houses the world's most complete collection of Jim Henson artifacts.

The interior of this Serbian royal family's mausoleum is covered with exquisite mosaics.

A collection of more than 12,000 shoes, displayed in a building shaped like a shoebox.

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

An ancient stone fortress considered by many to be the eighth wonder of the world.

The small sanctuaries lie just off the beaten path near one of Bhutan's most famous attractions.

This dazzlingly turquoise mountain lake was created in the wake of a natural disaster.

Mural made of 100,000 pieces of hand blown glass, and until recently, the largest glass mural in the US.

This church carved into the rocks is full of enchanting stone statues.

At the right time of day, sunlight floods through the roof of this cave and illuminates the small pavilion hidden within.

Ancient structures used to make and preserve ice in the deserts of Persia.

The cluster of igloo-like domes forms the remains of an ancient burial ground.

A total of 999 stairs lead visitors through a massive hole in a mountain known as the Gateway to Heaven.

Revel in the Victorian splendor of the world's oldest eating establishment inside a museum.

The ruins of a pre-Columbian fortress city so secure it held off the Spanish conquistadors for over 20 years.

The remains of a medieval city loom in one of the most isolated desert regions of Turkmenistan.