Ruins battered by centuries of war and disaster offer a wondrous glimpse of medieval Ireland.

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

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

A rocky Irish outcropping with a history of wealth, conflict, and ruin.

The enchanting archway is the only surviving portal into Dublin's lost medieval wall.

These imposing walls and towers look more like the ruins of a fortress than a monastery.

The oldest inn in Kilkenny was established by the first convicted witch in Ireland.

A remarkably intact castle that once was the largest in Ireland.

A moody and picturesque riverside ruin overgrown with vegetation.

Dublin's "Dead Zoo" serves as a window to Victorian museum design.

Danish tourist destination well known for open stalls where vendors sell marijuana on the street.

Copenhagen's celebrated theme park and gardens.

This museum housed in a former brothel explores the past and present of sex work in Amsterdam.

Museum preserving torture methods from the past.

Climb inside an iron crystal magnified 165 billion times its normal size.

The topiary maze at the Habsburg hunting lodge.

Walk through Czech history in Prague's largest graveyard.

Macabre astrological automaton clock dating to the late 1400s.

One of the largest underground systems runs under Canada's largest urban center.

A gorgeous mural outside a beloved D.C. restaurant pays homage to famous Black Americans.

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

D.C.'s first central library was born out of a chance encounter with the philanthropist whose name it bears.

Largest Roman Catholic church in North America.

The national park was once a plantation estate.