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

A forgotten "city of water" underneath the famous Trevi district.

A burial vault located under Tiber Island in the middle of the Italian capital.

The spot where the fascist dictator made some of his most famous speeches including declaring war on Britain and France.

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

This large, circular tomb is the final resting place of the first emperor of Rome.

This 1st-century CE Roman bath sits under a carpark.

If James Bond bungee-jumped off the side of a 720-foot dam, would you do it too?

The train platform where Jews were sent to concentration camps is now preserved as a Holocaust memorial.

Artistic tombs, monuments, and a beautiful "Hall of Fame" lurk inside this cemetery.

An ossuary built in 1210 to collect bones from the Ospedale Maggiore of Milan.

Ancient human remains unearthed around the iconic monument.

65 million-year-old chalk outcroppings mark the end of the Jurassic Coast.

This Roman quarry once held secret masses and smuggler's contraband and is now home to rare species of bats.

A local museum honors the overlooked discoveries of Mary Anning, one of the first professional fossil hunters.

Cliffs full of fossils at the portal to England's Jurassic Coast.

This commemorative stone was erected near the first Scout campsite.

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

Burial grounds for more than 1,000 bodies deep under the modern town of Rabat.

Three floors of musical instruments coming from all corners of the world and hundreds of years of musical history.

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

This man-made waterfall was designed to help improve access for spawning salmon.

The animals wander freely amid this gorgeous stretch of nature.

The ancient mosaics here are considered among the finest in the world, and serve as a stunning record of Greco-Roman daily life.