This remarkably well-preserved Egyptian plinth is pretty well traveled for a giant piece of stone.

Ancient serpentine sacrifice holder that has stood the test of time.

A fountain standing as a testament to a doomed alliance.

Pilgrimage site for star-crossed lovers.

An ancient Egyptian temple in the middle of Madrid, Spain.

Madrid's romantically ornate crystal palace has been offering shelter to plants and art for over a century.

Commonly acknowledged as the only public monument to the Devil himself.

A large grotto built in the 16th century amidst Florence's famous Boboli gardens.

This private skyway is filled with art and was expanded explicitly so that Hitler could appreciate a river.

In Florence's great Duomo, a 26 foot fresco honors a mercenary famous for attacking Florence.

Renaissance hospital featuring a rotating door into which unwanted babies were dropped.

A lover's walk between hilltop towns, decorated with graffiti love notes.

The bomb-ravaged remains of of a colossal Neptune.

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

Two very green residential towers cleaning the air in one of Europe's most polluted cities.

Old batteries and frog skeletons reside in this lakeside monument to Alessandro Volta.

A 14th century bridge built as a fortress, where the devil lurks on one of its towers.

Bordered by forest on three sides and the ocean on the other, the Great Dune of Pilat is the highest sand dune in Europe.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

Protecting the dead from opportunistic body snatchers.

360° views of the city plus five floors of optical illusions and hands-on science.

The final resting place of soldiers' loyal canine companions.

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

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