An incredible mosaic-lined monument said to have held the remains of an ancient Roman empress.

This triumphal 16th-century arched gateway leads to the oldest street in Palermo.

A whale rib was used to advertise the store by the arch that offered exotic goods from far away.

In the past, Renaissance sex workers were encouraged to entice customers on this bridge.

A copy of the famous statue can be found in this Florence piazza, along with one of the most breathtaking views of the city below.

Geometry and mystery come together in an epic show of octagonal masonry.

Italian poet Dante Alighieri is entombed in this small mausoleum in Ravenna, and his hometown of Florence has never been too happy about it.

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

Over 50 exquisite hand-painted Renaissance maps decorate a Medici storage room.

A statue representing a lost Roman profession that was vandalized for centuries.

Also known as the Square Colosseum, this building is a prime example of fascist-era rationalist architecture.

Installed in an act of one-upsmanship, the annual sundial in this church is also a symbolic victory for the Gregorian calendar.

This massive redwood tree has stood in Northern California for nearly 2,000 years.

Bring your own cardboard to the slippery slopes of concrete hidden in a neighborhood park.

Underwater art project will double as a massive artificial coral reef to help regenerate the damaged ecosystem.

The ruins of a monastery that dates to the 7th century.

One of America's founding fathers lived in this London lodging between 1757 and 1775.

An immersive Māori village where you can learn history and heritage through dance, ceremony, song, architecture, and food.

A simple but powerful tribute to the 20 victims of the 1692 witch trials.

This cannonball embedded in the side of an Edinburgh house once served a surprisingly pedestrian purpose.

The displays in this off-the-beaten-path museum highlight the holistic, indigenous methods of healing.

The former house of an anthropologist couple displays Lacandón Maya artifacts in a homey atmosphere.

An elaborate Mayan city shrouded in alien conspiracy revealed the tomb of Pacal the Great.

The enigmatic skull gazes out over the ruins of a once-great Mayan city.