Frederiksborg Castle might be one of the world's largest fortresses, but it's also undoubtedly one of the most beautiful.
At a length of 3,448 feet (1,051m), Burghausen Castle is said to be the longest fortress in the world, as confirmed by Guinness World Records.
With over a thousand years of history, Prague Castle is one of the world's most spectacular architectural gems.
As one of the largest hilltop fortifications in all of Europe, Königstein Fortress is a majestic example of late Gothic, Renaissance and Baroque architecture.
The Alhambra is perhaps Spain's most iconic castle and its beauty is undisputed.
In the heart of this ancient city, you'll find a medieval castle of an unmatched scale.
Built in the 13th century, Malbork Castle is one of Poland's most imposing pieces of architecture and appears almost untouched since its inception.
One of the world's most imposing pieces of architecture, Chittorgarh Fort's scale is hard to believe.