This equestrian statue of Constantine the Great has been the subject of criticism for centuries.

Once the grandest synagogue in medieval Spain, it now stands as a memorial of the 15th-century Jewish exile.

Amid the sprawling Defense Intelligence Agency Headquarters is one of Washington's least accessible museums.

Occupied for six centuries by Franciscan Order nuns, this monastery is an amazing ode to Catalán Gothic architecture.

This hidden oasis features a stunning view of the Hudson River and the Palisades from a castle-like museum.

These wire animal sculptures commemorate the exotic inhabitants that once called the Tower of London home.

This monument dedicated to the legendary American showman can be found in Scotland's largest city.

This iconic Peak District ridge was once one of the busiest roads in medieval Britain.

A historic, reportedly haunted pub that provided inspiration for several famous adventure novels.

This Norman castle was once the site of a Victorian-era prison, and now exists as a luxury hotel.

Heralded as the world's first theater, these ruins are often overlooked as they reside in the shadows of the Acropolis.

An 18th century fountain and two columns are all that remains of Rome's forgotten river harbor.

These artifacts were discovered during the construction of the airport, with some dating back to the Neolithic period.

This fortress dates back to the 6th century and is also the site of a controversial abandoned restoration project.

This house was home to a succession of park keepers for more than 90 years, but in all that time, it never had a toilet.

This police call box harkens back to an era of pre-radio communications, and has a rather unique feature.

This palatial botanical garden is home to one of the largest pipe organs ever installed in a private residence, and a piece of Wood's cycad.

A tiny, unmarked beer and whiskey bar above an Ethiopian restaurant in West Philly fails to conceal live bluegrass.

The shop where the girl who inspired the beloved character once bought sweets is now a book-themed commercial curiosity.

Brass bricks outline the locations of Edinburgh's lost, lively market stalls.

A local student's chance encounter with Keith Haring led to the creation of one of Europe's largest murals.

Often mistaken for an office building, inside this venue is an amazing collection of Native Alaskan art.

The singer, actor, and activist lived here during his final years, and now it’s a museum dedicated to his legacy.

Alexander Hamilton’s creation caused quite a bit of controversy.