The Polish capital has had a deep connection to its guardian mermaid for almost a millennium now.

The remains of an ancient city-state along the Silk Road.

Where the father of Persian poetry is laid to rest.

This "tower of death" has acted as an observatory, a religious hub, and an executioner's lair.

Ancient barriers wrap around what was once an important stop along the Silk Road.

Light still pours into the ruins of this ancient Islamic observatory.

The Avenue of Mausolea is a series of grand palatial tombs.

One of the world's tallest statues is also one of its most hated.

Home of the future Emperors of Russia.

Stalinist skyscraper built with help of cryotechnology.

The "Mystery and Company of Merchant Adventurers" is an Elizabethan-era hangout in Moscow.

The avant-garde design was able to bypass strict Soviet regulations on architecture.

A modern tower, symbolizing the legend of a golden egg on top of the tree of life.

In Kazakhstan, a colorful cathedral with many lives once survived the most powerful earthquake in the region.

Nicknamed Kazakhstan's Grand Canyon, this natural wonder lies east of Almaty near the Chinese border.

Submerged trees jut ghost-like out of an idyllic turquoise mountain lake.

Built entirely of interlocking pieces, construction of this Chinese Muslim house of worship required zero nails.

Lonely minaret stump of a destroyed city.

A boulder carved into the shape of the cosmonaut's head.

Extremely isolated Silk Road caravanserai in the middle of nowhere.

This mountaintop observatory is home to one of the world's largest reflective telescopes.

These wooden balconies that are both decorative and functional.

The largest salt farm in the Canary Islands is located at the foot of an active volcano.

Hundreds of caves once used to store grains and animal feed.