This hidden Art Nouveau courtyard is an opulent feast for the eyes.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

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

A small museum that celebrates the history and culture of the LGBTQ community in England.

A legal loophole makes it possible to get away with murder within this 50-square-mile section of Yellowstone.

This temple was constructed entirely by Roman soldiers.

This tidal island, a sacred site in early English Christianity, was the target of a notable Viking invasion.

This nondescript building hides an entrance to an underground nuclear tunnel system.

Just another ancient, mysterious Irish stone circle.

A tribute to the incredible generosity the Choctaw Nation showed the Irish people during the Great Famine.

An oddly conical beacon perched atop beautiful Irish cliffs.

A stunning medieval castle owned and restored by the famed actor Jeremy Irons.

An important landmark in the history of algebraic logic.

This cemetery features modernist statues as strange as its name.

This semi-secret storybook hedge maze is also the oldest garden in the city.

This 6th-century church honors St. Tudno, the patron saint of Llandudno.

A collection of comics, graphic novels, animation and caricatures devoted to exploring this often overlooked art form.

This small corner bar is home to a rare 1930s dance organ that still plays tunes for one Euro.

Drink among marionettes at this pub inside a historic puppet theater.

This 2,000-year-old tree inspired the nursery rhyme "Rock-a-bye Baby."

A tiny metropolis resides inside this student housing complex.

A replica of a 17th-century map of the stars stands in the courtyard of a Belgian university.

This statue of a studious young woman stands at the site of Leuven's first college to accept female students.

A small statue commemorates a centuries-old event that still hangs over the people of Leuven.