Preserved Inca city and site of the last Inca stronghold against the Spanish conquistadors.

A deadly ancient portal to the underworld.

These tombs were built into the side of a mountain so that ancient angels could reach the dead.

Roman ruins top white travertine terraces formed by ancient hot springs.

Climb a set of vertiginous stone steps to the top of this impressive ancient edifice.

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

A fountain standing as a testament to a doomed alliance.

Large miniature theme park with 100-plus models.

A small etching on the white marble parapet was written in runic script by a Viking mercenary.

A marvel of Byzantine engineering under the streets of Istanbul.

This unassuming tree stump reportedly traces its roots to the famous pharaoh queen's reign.

This ancient structure is widely thought to be the oldest intact pyramid in the world.

These Egyptian statues have survived for 3,400 years and were an acoustic wonder of the ancient world.

The medieval center of the Islamic world was also once the seat of Saladin's sultanate.

Slum Settlement Filled With Mountains of Garbage.

Standing atop 2nd-century Roman ruins, this church is one of the oldest and most iconic in Old Cairo.

The massive cave church of Cairo's Zabbaleen community is one of the largest Christian churches in the Middle East.

An ancient instrument used to measure the waters of the Nile so Egyptian farmers would know whether to expect famine or flood.

Once the gateway to the utopian dream-village of a Civil War embalmer.