Citadel of Qaitbay in Alexandria, Egypt

Construction of this austere fortress on the Mediterranean Sea began in 1477 after Sultan Al-Ashraf Qaitbay learned of Ottoman troops advancing toward Alexandria.

Bojnice Castle in Bojnice, Slovakia

According to written records found at the Zobor Abbey, this Romanesque castle may have first been built as a wooden fort as early as 1113.

Château de Chenonceau in Chenonceaux, France

Surrounded by manicured formal gardens, Château de Chenonceau appears as though it’s elegantly floating over the reflective Cher River.

Red Fort in Delhi, India

Mughal Emperor Shah Jahan laid the foundation of the Red Fort, or Lal Qila, after moving the empire’s capital from Agra to the newly built city of Delhi.

Château de Chambord in Chambord, France

A magnificent display of French Renaissance architecture, Château de Chambord boasts an impressive 440 rooms, 282 fireplaces, and 84 staircases.

Pena National Palace in Sintra, Portugal

Influenced by Eastern and European Baroque styles, the Pena National Palace represents the eccentric and colorful flair of 19th-century Romanticism in Portugal.

Neuschwanstein Castle in Schwangau, Germany

King Ludwig II of Bavaria commissioned Neuschwanstein Castle in 1868 as an escape from the public eye and political turbulence.

Castel del Monte in Andria, Italy

Much mystery surrounds the Castel del Monte and its purpose for being built. Emperor Frederik II ordered the construction of the citadel in 1240 in a rather remote area of southern Italy with no means of protection.

Frederiksborg Castle in Hillerød, Denmark

Located on three small isles on the Castle Lake, the distinguished Frederiksborg Castle was built as a symbol of King Christian IV’s power as ruler of Denmark and Norway.

Windsor Castle in Windsor, England

The oldest and largest inhabited castle in the world, Windsor Castle has acted as an official royal residence for the United Kingdom monarchy for more than 900 years.

Edinburgh Castle in Edinburgh, Scotland

Standing tall on the crags of Castle Rock, Edinburgh Castle exudes a sense of authority and nobility throughout Scotland’s capital.

Vianden Castle in Vianden, Luxembourg

Overlooking the River Our in northern Luxembourg, Vianden Castle was first built on the site of an ancient Roman watchtower between the 11th and 14th centuries.