A rare double mill nestled along the banks of the Aa river.

Portraits of musicians line Oude Binnenweg, the jazziest street in the city.

Established in 1638 to battle the Black Death, Hortus Botanicus Amsterdam is a treasure trove of rare flora.

The mirrored section takes the shape of Hebrew characters when viewed from above.

The attic of a four-century-old canal house hides a clandestine church.

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

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

A network of ancient Egyptian tombs built into the cliff face along the Nile.

This 7th-century monastery was sacked by Saladin.

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

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

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

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

Found in the waddenzee, this propeller has been put on public display as a reminder of the Second World War.

A martyred saint built a nunnery and school for girls here known as the "Parthenon."

This Ottoman-era Greek Orthodox Church was built to honor Agia Pareskevi, a Christian saint.

An ancient Greek monument and a Byzantine church coexist inside this cave.

View the ancient remains of buildings and the ancient "River of Hades" before hopping on a train.

A former military hospital is now used to study and preserve artifacts of the Acropolis.

Fortified medieval tower house with lovely roof garden.

Swiss vineyards in a UNESCO heritage site.

The world's tallest church tower reveals a spectacular view to anyone up to the task of climbing the daunting staircase.

This abandoned shopping arcade has new life as an art installation.

A Portuguese Jewish cemetery filled with stunning grave monuments that date back to 1614.