The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

A particularly disconcerting tribute to Irish martyrs.

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.

Ancient rock-hewn town that witnessed key events of Georgian history.

The ruins of a town wiped out by the second-largest earthquake in recorded history.

The ruins of a medieval monastery named after a type of tree.

Mortarless walls that stretch for miles are a lovely solution for creating grazing land in the harsh terrain of the Aran Islands.

This ancient Irish tower could easily have stood in for Rapunzel's prison.

An ancient neolithic tomb that only sees the sun twice a year.

The ancient tomb acts as a calendar that keeps perfect time.

These gigantic skeletons tower over visitors and provide insight into the creatures that once ruled over Ireland.

Dublin's most modern, visually spectacular bridge is modeled after Ireland's national emblem.

Experience what life was like in Ireland during the Viking and medieval ages.

The mummified heart of a saint lives on in this church—after a brief hiatus when it was stolen.

Towering basalt columns, a creation of fire and ice.

A natural dome made of volcanic glass in Inyo National Forest.

Aqueducts have dramatically changed this old lake, now home to tufa towers and its very own species of tiny brine shrimp.

This spectacular track has run continuously since 1882.

An oddly specific collection of handmade dolls remembers the women of the White House.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

The little-known second castle that William the Conqueror built in York.

A pair of large white marble lions guard this stretch of the Mojave Desert, and it is utterly mysterious how they got there.

The abandoned train depot now doubles as a well-placed rest stop for those who take the road less traveled.

L.A.'s oldest operating bowling alley is a beautifully restored homage to its speakeasy days.