This curious, round temple is the oldest still-standing marble building in Rome.

This one-of-a-kind Roman arch is not actually dedicated to the god Janus.

Destruction from Armenia's 1988 earthquake inspired an artist's sculptures of scrap metal.

Designed as a labyrinth, this subterranean prison was crafted without bars or doors.

This is the oldest Roman-made bridge in the city still existing in its original state.

These hut foundations are believed to be the residence of Romulus, founder of Rome.

An ancient Roman temple first dedicated to an emperor's wife is now a church.

This ancient market is often referred to as the oldest shopping mall in the world.

This mountain trail inspired Nietzsche to complete his magnum opus.

In the early Roman Empire, people deemed traitors and criminals were tossed to their deaths from this rock.

An unusual double-stelae obelisk with ancient and mysterious origins.

This small, ancient Roman temple was once a church dedicated to the patron saint of penitents.

This pair of running lions engraved on animal bone is one of the earliest artistic depictions of big cats.

On this romantic tidal island reachable only at low tide the tomb of a famous French writer overlooks the sea.

This 18th-century sundial was designed to calculate the date of Easter each year.

The world's tallest bridge is also possibly the most elegant.

The oldest and smallest cemetery in Paris is only open to the public twice a year.

A majestic lion statue guards this Parisian botanical garden, and feeds on an unsettling item.

Indents in the pavement are all that remain from a grisly death machine in Paris.

A living descendant of the famous tree that helped Isaac Newton develop the theory of gravity.

These ancient rune stones plucked from the countryside now call this university park home.

The eerie ruins of this feudal fortress witnessed the execution of 60 conspirators in 1387.

This building has survived for more than a century and remains virtually untouched.

An ornate "graveyard" for some of the country's forlorn building relics.