The oldest cemetery of modern-day Athens blends the modern and ancient worlds.

An ancient octagonal weather station named for the eight Greek gods of wind.

This ancient hydrological marvel is now the base of a modern outdoor cinema.

The railway carts travelers to central Athens's highest peak, which offers stunning vistas of the city.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

The Cycladic architecture makes this Athens neighborhood feel like an island paradise hidden in the shadow of the Acropolis.

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

The city-sized home palace of one of ancient Egypt's most powerful rulers gives us a rare look into the lives of the epoch's rulers.

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

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

One of its engravings is believed to be among the first representations of medical and surgical instruments.

The largest known Ancient Egyptian obelisk.

A preserved oasis with traditional Andalusian-style architecture and beautiful views of the Nile.

In Egypt's expanding metro area, many of the neighbors are dead.

Known as the Sistine Chapel of Egypt, this tomb houses some of the most well-preserved paintings in Egypt.

A massive work of modern art that appears to be a crop circle in the middle of the desert.

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

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

One of the most well-preserved temples of ancient Egypt.

A quirky bookstore hidden beneath a sea of whitewashed Greek villas.

No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

This Costa Rican chapel is the most metal church in the world, literally.

The sister plane of the C-123 shot down during the Iran-Contra Affair has found a new purpose in retirement.

An unassuming tomb houses an important milestone in Indian architectural history.