Colombia's first concrete structure doubles as a replica of Versaille's Petit Trianon Belvedere and a symbol for development.

A large stone map of Arkansas awaits visitors to its highest point.

Pennsylvania's highest point is spotted with boulders which were pushed to the surface by nothing but cold.

The grandson of a Kiowa chief created what has become the iconic symbol of a city on the Plains.

This historic Ellinwood hotel is also home to underground tunnels that were a popular haunt during Prohibition.

An extraordinary collection of 18th century anatomical waxworks.

The remains of an ancient Roman city are hidden underneath Bologna's beautiful public library.

A striking memorial recalls thousands of Bolognese men and women killed fighting fascists in World War II.

In the world's oldest university is a stunning 17th century anatomical theater carved from spruce.

Time has been frozen at this station since the bombing in 1980—or so it was believed.

This 2,000-year-old Doric bridge is still open to pedestrian traffic to this day.

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

These spartan apartments are provided to clergymen visiting Vatican City.

Hidden beneath the famous St. Peter's Basilica is a veritable city of the dead that may hold the remains of St. Peter himself.

Historic fortifications form the boundary of Vatican City, but it’s not entirely surrounded by walls.

Breathtaking and huge 430 year old maps of Italy.

An 18th-century post box used to alert the church of sick and ailing foreign pilgrims.

The Italian revolutionary's legendary wife is portrayed on horseback waving a gun and holding her child in this memorial on the Janiculum.

Among the busts of heroes of the Roman Republic of 1849, there is also a statue of a boy and his dog.

More sculpture than building, this architecturally significant temple was built on the spot of Saint Peter's crucifixion.

Brass cobblestones mark the places where individual Holocaust victims were taken from their homes.

A small cell adjacent to this church was once the bedroom for a renowned saint.

The final resting place of the poets Shelley and Keats.

The only "Egyptian" pyramid in Europe and the legendary tomb of Remus.