This impressive working clock made of 16,000 plants changes its flowers twice a year.

A 98-room castle in the middle of Toronto that bankrupted a 19th century electricity multimillionaire.

This restored opera house is named after a soprano known for tragic romance, exile, and a truly uncomfortable wedding.

A beautiful memorial tells the story of a formerly enslaved woman whose kindness shaped a burgeoning city.

Roman-era ships unearthed...

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

Dublin's most modern, visually spectacular bridge is modeled after Ireland's national emblem.

The somber sculptures commemorating Irish Famine on the river Liffey in Dublin.

The only remaining arch of the oldest stone bridge in Rome stands in the middle of the Tiber.

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

Ancient ruins hidden underneath a modern luxury hotel.

An ancient Egyptian obelisk is now used to commemorate fallen Italian soldiers.

Believed to be the remains of the lost Temple of Minerva, this nymphaeum has been known by its misnomer to this day.

A monumental fountain in Rome features a large statue of Moses that has been criticized for centuries.

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

A detailed pachyderm supports Rome's smallest Egyptian obelisk.

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

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

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

A sculpture serving as an homage to Pope John Paul II.

The remains of this 2nd-century Roman temple are incorporated into a modern building.

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

Romans decided this 16th-century "talking statue" was so ugly, they named it after a primate.

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