It took more than 300 years to build this church, which is home to two sacred vessels believed to hold the blood of Christ.

The oldest church in Mantua was buried for centuries under the facades of other structures.

A new sculpture calls attention to climate change in the centuries-old city it threatens.

According to tradition this is the oldest church in Venice, but its actual age is a mystery.

This Roman statue is missing a limb from when the Venetians stole it from Constantinople during the Crusades.

Two stone columns flank the grand Venice square, but there were supposed to be three.

An extensive collection of reliquaries containing the bones of saints housed in the largest Catholic church in Venice.

Thousand-year-old Viking runes adorn an ancient Greek lion at the entrance to the Venetian Arsenal.

Go inside to really appreciate this 500-year-old technological masterpiece.

This palatial spiral staircase was so unusual the name "snail" was given to the noble family who built it.

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

Hundreds of thousands of concrete bunkers crowd Albania long after the fall of Communism.

This ominous Albanian fortress houses tanks and downed planes as a reminder of their victories over Western imperialism.

A naturally beautiful, seemingly bottomless deep blue spring.

This abandoned Greek island was the last active leper colony in Europe.

A minotaur, a labyrinth, and a dubious restoration pull in visitors from around the world.

Rock carving created 1,300 years ago 75 feet off the ground.

Mysterious standing stone formations looks like a petrified forest.

This small shrine is dedicated to the designer of the first Russian fighter jet and his brother, who became Chairman of the Presidium of the Supreme Soviet.

At this rare mosque in Tbilisi, Sunni and Shia Muslims pray side by side.

A museum glorifying the life of Stalin, located in the city of his birth.

This architecturally eclectic fortress witnessed centuries of bloody turmoil, including the massacre of its ruling clan.

A cluster of historic bathhouses built on the famed hot springs that gave the Georgian capital its name.

A small but hugely whimsical theater where marionettes play out the "The Battle of Stalingrad."