The smaller of the three towers of San Marino is a former prison inaccessible from the ground level.

High in the clouds of San Marino sits an ancient tower with some curious prisoner graffiti.

Historic fortifications form the boundary of Vatican City, but it’s not entirely surrounded by walls.

Hidden beneath the famous St. Peter's Basilica is a veritable city of the dead that may hold the remains of St. Peter himself.

This equestrian statue of Constantine the Great has been the subject of criticism for centuries.

An ancient Incan convent on Lake Titicaca's Island of the Moon.

Explore the ruins of war and maritime history along this gorgeously ferocious North Atlantic seascape.

The city of Halifax still bears the scars of the largest explosion prior to the atomic bomb.

The profile of one ill-fated deacon was emblazoned forever on this church window during the Halifax explosion.

This historic cemetery stopped accepting bodies before many Canadian cities were founded.

No one knows the origins of the mysterious stone ruins discovered on a hillside in Halifax.

A beautiful, water-filled quarry that has become a popular haunt for swimmers and artists.

Sculptures, jams, and the wild west collide at this folksy retreat.

This architectural onion has an original 1930's Jerry O'Mahony dining car at its core.

A decidedly out of place statue memorializes the Blues Brothers characters at this water bottling plant.

The 32nd president's sprawling cottage sits on an island enclave jointly managed by the U.S. and Canada.

A rare opportunity to drive across the ocean floor.

The highest tides in the world come in and out here twice a day, allowing you to essentially walk along the ocean floor.

Built more as a work of art than living quarters, this cottage has withstood the test of time.

Everything in this two-story house—down to the mounted deer head on the wall—was carefully crafted from concrete.

The oldest pub in Ireland may also be the oldest surviving bar in the entire world.

Behemoth, cannon-like telescope operated by generations of Irish earls.

The world's tallest box hedge is found in a delightful garden.

A strange egg in a mucky bog of western Ireland marks the spot of an aviation milestone.