A historic building houses one of the most important archaeological institutes in Europe.

These ancient ruins hide in plain sight next to a dessert shop.

This building served as the first customs house in modern Greece.

This church is dedicated to the patron saint of seafarers.

This building was once the most magnificent mansion in Nafplio.

Underneath one of the region's most historic roads lies the home of Plato's successor.

A tiny Greek Orthodox church from the Ottoman era hides on a busy city street.

The ruins of an ancient fortification wall sit in front of and underneath this boutique hotel.

The heads and relics of 179 monks slaughtered by pirates are on display within this Ceonobic Monastery.

The ruins of this ancient fortification wall sit in the middle of a quiet, residential intersection.

This seaside sanctuary was once one of the most important religious sites for women in ancient Greece.

According to legend, this cavern holds the passage that Persephone used to travel to and from the underworld.

Only open for two days a year, this church links ancient Greek and modern Christian celebrations.

A seaside castle complex that stood through centuries of conquests.

After being destroyed by two separate fires, this monastery is now home to a small zoo and relics from dozens of saints.

This sixth-century church housed an icon with eyes so beautiful legend has it they inspired the name of a Greek city.

A staircase made of gravestones leads up to this church built into a giant rock.

The Greek War of Independence was declared at this medieval Byzantine sanctuary.

This 18th-century former mosque held the first Hellenic Parliament.

A preserved portion of an ancient Athens barrier is displayed in a hotel basement.

Preserved portions of Athens's ancient defenses are on display in a subterranean parking garage.

The ruins of an ancient mansion sits in front of and underneath a contemporary art gallery.

This fairytale-looking castle is a wonderful example of Greek neo-Gothic architecture

Step inside an ancient beehive tomb built for a mysterious cult hero.