One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

A cathedral resurrected from the ashes of one of Europe's greatest urban fires.

The de facto symbol of Copenhagen is this bronze fairytale which cannot seem to keep its head for very long.

Opulence and fantasy collide in this royal chair which is supposedly made with unicorn horns.

Breathtaking and huge 430 year old maps of Italy.

Despite attempts by local police to discourage it, Beatles-inspired graffiti has been a means for artists to air grievances for decades.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

A mocking tribute to the past and modern leadership of Prague.

Looming communist pillar with a Czech twist.

Ancient serpentine sacrifice holder that has stood the test of time.

This remarkably well-preserved Egyptian plinth is pretty well traveled for a giant piece of stone.

A marvel of Byzantine engineering under the streets of Istanbul.

A mysterious ancient cemetery with Roman sarcophagi and Lycian inscriptions.

This quaint Hungarian railway system is operated exclusively by children between the ages of 10 and 14.

Possibly the world's largest hourglass only needs to be reset every New Year's Eve.

This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

This Budapest bar allows drinkers to leave their mark on the walls, floor, and even ceiling.

Giant eggs, walls of bread, and nightmare surreality mark the largest collection of works by Salvador Dalí.

This tin chapel was built by POW's during World War II and is painted to look like something much more grand.

Northern Ireland's Brobdingnagian stepping stones.

The ancient tomb acts as a calendar that keeps perfect time.

The modern birthplace of Irish freedom.

Amidst the bustling streets of Dublin, there is a hushed garden that is dedicated to "All those who gave their lives in the cause of Irish Freedom."