A derelict bit of infrastructure from the canal that once ran through D.C. is landlocked in the heart of the city.

A bas relief commemorates the "Nuns of the Battlefield" who cared for soldiers on both sides of the conflict.

The Byzantine, pre-Columbian, and medieval art at this stately mansion are some of the most under-appreciated collections in D.C.

Home to items never before seen by the public.

With over 100 jam-packed rooms to explore plus elaborate tea services and events, the Mansion on O Street is a hidden treasure.

The graveyard holding the remains of George Washington's slaves was forgotten for nearly 200 years.

The only recreation of William Shakespeare's indoor playhouse.

A colorful square marks the heart of the city's LGBTQ community.

A key producer of charcoal iron in the early 1800s, the structure still stands today.

A delightful park featuring homemade scale replicas of dinosaurs, tucked away in the Tennessee mountains.

This bridge is the first to be made entirely from iron, but designed like it was still made of wood.

This charming English house was once the home of England's most famous poet.

The highest peak in all of England is plagued by dangerously fickle climate shifts.

A stone copper was sculpted on the wall of the Carlisle Cathedral to honor a local hero.

A six-ton wedding present for the King of the Scots.

The most loyal of little dogs, or a Victorian era publicity stunt?

The tomb of one of Scotland's bloody historic villains is a magnet for bumbling desecrators.

Overlooked by many, the two famous Scottish warriors guard the main gate of Edinburgh Castle.

The final resting place of soldiers' loyal canine companions.

A statue in the heart of Edinburgh honors a bear that served in the Polish military during World War II.

Remnants of the 16th-century defensive wall still stand unassumingly within Edinburgh.

This 17th-century street hidden beneath Edinburgh was once a breeding ground for the black death.

A sweet symbol marks the place where torturous executions were once carried out.

Protecting the dead from opportunistic body snatchers.