A 19th century artistocrat's mansion, turned into a library, hidden in a modern library.

Museum dedicated to the terror regimes of Hungary.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

This Budapest bar allows drinkers to leave their mark on the walls, floor, and even ceiling.

Also known as the Blue Church, the building was consecrated to the daughter of Andrew II.

The inverted pyramid design of this station stands out amid Bratislava's urban landscape.

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.

A small museum filled with over 1,000 clocks, and one particular clock calibrated to run until the year 9999.

Vienna's diversity-themed traffic lights were inspired by the Eurovision Song Contest.

Vienna's giant wonder wheel had a starring role in one of the greatest noir movies of all time.

Baroque celebration of the end of the Great Plague of Vienna.

The beautiful baroque library of the Hapsburg empire.

The library houses an incredible collection of some of the world's most impressive books and manuscripts.

The remains of this 2nd-century Roman temple are incorporated into a modern building.

A massive marble foot is tucked away in a small alley near the Pantheon.

A detailed pachyderm supports Rome's smallest Egyptian obelisk.

Museum dedicated to literary greats of the Romantic Period is also the home in which Keats met his untimely end.

This Roman arch marks the location of an ancient gate at one of the Seven Hills of Rome.

2300-year-old Roman road connecting the empire.

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

This ritzy Italian market is built around a statue of an unforgiven heretic who was burned for his belief in an endless universe.

Breathtaking and huge 430 year old maps of Italy.

Historic fortifications form the boundary of Vatican City, but it’s not entirely surrounded by walls.