Once the legendary capital of the Dacian Kingdom, this city has been reduced to mere ruins.

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

The Grand Lodge of Ireland is one of the oldest in the world, full of fantastical, elaborately themed rooms.

A nun spent 16 years painting the stunning Celtic mural that covers the interior of this WWI memorial.

A meandering boardwalk across the bogland leads to a "stairway to heaven" with sublime views.

Impressive mining ruins overlook a spectacular view of Ireland's Copper Coast.

Traveling this mountain pass reveals quaint stone buildings, stunning Irish scenery, and a bridge said to grant wishes.

Perfectly preserved ancient monastery in an impossibly dramatic location on a rocky island in the Atlantic.

The largest portal tomb in Europe has a capstone weighing around 150 tons.

An ancient chamber filled with wonderful rock art and a Neolithic carving of a human face.

This Irish museum in a historic 19th century market pays tribute to the glory of butter.

An oddly conical beacon perched atop beautiful Irish cliffs.

The skeleton of a whale that beached itself in this Irish town is now on display in their public park.

One of the most popular megalithic sites in Ireland stands as a humbler version of Stonehenge.

A tiny microvalley etched into the side of Knocknarea Mountain hides another world.

This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

This Slovak bridge is known both for its connection to a national uprising and its UFO-shaped eatery.

This Slovakian statue of an emerging sewer worker might just be a bronze peeping tom.

The deepest sinkhole in Central Europe comes with a grisly tale and an unusual nickname: “The Stepmother Abyss.”

The palace window through which Protestant nobles flung two Catholic regents, thus sparking the Thirty Years' War.

Macabre astrological automaton clock dating to the late 1400s.

This 11th-century structure is one of the oldest churches in Romania.

The footprint of a frustrated devil in Munich's Cathedral.

Daily jousts and dancing barrel makers in Munich's mechanical clock.