Largest cave system in Africa.

Local lore says a serpent-like beast lurks in the deep basin below the falls.

Over a million items cram the shelves at Africa's largest shop of used and rare books.

A South African bar inside a hollowed out 6,000-year-old Baobab.

Supposedly this Ethiopian chapel holds the Ark of the Covenant, guarded by virgins who cannot leave the building.

Reaching the "Church in the Sky" requires scaling the cliff face of a sandstone pinnacle with a 650-foot drop.

An Ethiopian "Jerusalem" featuring a church hewn out of a single rock.

An otherworldly restaurant perched on the edge of a jagged cliff next to a medieval holy city.

This museum is a full-size replica of an original church constructed during the 13th-century.

The world's largest and most outstanding marl lake regularly changes color.

Legend has it this spring formed at the spot where a medieval Swedish king was killed.

A tiny town hall—in Sweden's one-time capital—might be the smallest in Europe.

These limestone cliffs are associated with the Greek myth of Prometheus.

This church is considered the largest and most complete Saxon church in England.

This natural "sea of stones" was once used by the Romans as a quarry.

The colorful soil of Iran’s "Rainbow Island" attracts artists and nature lovers.

This historic church houses the grave of a Scottish soldier who fought in the Battle of Waterloo.

This fully restored synagogue explores the American Jewish experience along the old frontier.

270 million year-old forest of stone.

You can still find treasures on the pebbly beaches of one of the world's oldest jade-producing areas.

These mystical miniature houses bring a touch of magic to the New Jersey woods.

Templar knights fleeing persecution are said to have left this sword in stone as a landmark in 1307.

A rare survivor from the age of plagues.

Inside this cathedral is a shoulder bone belonging to the Patron Saint of Scotland.