Small ship votives hang from the vaulted ceiling of this port-side church with a Latin inscription on the wall.

Thousands of Haitians travel to the waterfalls to ask the Virgin Mary of Mount Carmel and her voodoo counterpart Erzulie for healing in a yearly pilgrimage.

Built in 1512, the oldest cathedral in the Americas.

The alleged house of the Virgin Mary is tucked away in a park and nature preserve on Mt. Koressos in Turkey and is holy to both Catholics and Muslims alike.

Picturesque intersection of witchcraft and ancient Christianity.

Lake within a lake.

A lake formed in the basin of a massive impact crater takes the shape of an unbroken ring when viewed from above.

A church of bones, decorated with 40,000 human skeletons.

A walk through the historic city center, under the streets of Seattle.

An abandoned Jazz Age dream home and con man's hideout in Death Valley.

Inhospitable caverns just beneath this island paradise offer insights into alien worlds.

An unrealized dream to wirelessly electrify the entire Earth.

17th century streets hidden under Edinburgh were once a breeding ground for the black death.

These azure waters were thought to lead to the Mayan Underworld.

The seamy, underground secrets of Portland's criminal past.

The deepest underground city in Turkey was designed to protect 20,000 people behind massive stone doors.

While not Turkey's deepest underground city, this subterranean redoubt is the largest.

A Nesting Doll of Churches.

Site of the largest impact event to occur over land in Earth's recorded history.

Experience a quartz crystal sound bath inside a storied, all-wood sound-chamber.

Unexplained bald patches in the landscape grow and recede over time, as though they are somehow alive.

Striking occult iconography on a medieval German church.

Beasts and branches swirl in sandstone carvings, interrupted by one strange creature.

This centuries-old pueblo church houses the body of a Franciscan friar who is said to be a rare "incorruptible" corpse.