Stalactites and stalagmites in a beautifully lit cave.

A striped 12th-century basilica sits in the countryside of Sardinia.

This weird, elephant-shaped rock also hosts two ancient tombs.

At an estimated 3,800 years old, this olive tree is one of the oldest on earth.

Mysterious tombstones thought to be remnants of Atlantis.

This one-of-a-kind archeological site is home to strange prehistoric ruins, the original use of which is still a mystery.

This elaborate hole in the ground was built as a sacred site for an ancient civilization.

A strange rock with a sinister reputation lurks within the crimson waters of this Scottish glen.

A single oak tree rises out of the waters of Loch Lomond.