What might look like a cliffside sacrificial altar at first glance is actually a stone compass pointing to cities and lighthouses all around the world.

This art center is way beyond your average pumpkin-carving operation.

A Spanish forest is filled with mysterious stone carvings.

An absolutely beautiful 200-foot stained glass installation traces the evolution of knowledge.

The writing studio of an American adventure author, built in the style of a medieval castle.

The unbelievably opulent home built for an infamous newspaperman.

This mysterious underground cave in Shropshire dates back to the 18th or 19th century.

The only swimming pool listed on the National Register of Historic Places is emptied and refilled each day with naturally filtered water.

Hundreds of mossy stones engraved with bits of philosophy, literature and random musings.

These haunting ruins belong to an ancient village that once had one hell of a view.

Founded by the famed children's book artist, this museum spreads an appreciation of the arts through picture books.

This cemetery has graves dating back to the 17th century, including the city's oldest carved tombstone and an ominous cryptogram.

Lithuania's outdoor sculpture trail of wooden folk art.

A trio of giant wooden megaphones turn up nature's volume in this Estonian forest.

Over 300 wood sculptures depicting characters from Slavic, Greek and Western folk tales fill this magical garden.

This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

Despite centuries of architectural innovation, this French castle is being built like it's the 13th century.

The oldest surviving wood-frame building in North America is still in the family.

Some wattle-and-daub, a Moorish mural, a glacial erratic, and a Giant named Gilbert.

A 16th-century horror show built in a lovely Italian garden.

Riding on a pair of architectural dragons, this Thailand temple holds murals full of lurid imagery.

This Russian religious complex is a Frankenstein's chapel that includes influence from almost all the major faiths.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

This replica Viking village was created for a film that was never shot and is now open to visitors.