The Alhambra towers over Granada, symbolising Spain's history. The Nasrid dynasty's founder, Ibn al-Ahmar, commissioned the hilltop palace and fortress in 1238.
Castillo San Felipe del Morro (El Morro) took nearly 250 years to build. Spanish builders began building the fort at the top of Old San Juan in 1539.
The formal gardens of Chateau de Chenonceau make it appear to float over the Cher River. The 11th-century structure was built by Henry II's mistress Diane de Poitiers.
King Carol I built a neo-Renaissance castle in Sinaia in the 1860s after being captivated by the Bucegi Mountains. Each of the 160 royal summer house rooms is themed.
Chapultepec Castle in Mexico City was the only North American royal castle. Viceroy Bernardo de Galvez ordered the fortress's construction in 1785 for New Spain's commander-in-chief.
In 1477, Sultan Al-Ashraf Qaitbay began building this austere Mediterranean fortress after Ottoman troops approached Alexandria. On Pharos Lighthouse ruins, castle plans were cleverly laid out.
To repel invaders, the Ogasawara clan built Matsumoto Castle in 1504. Warlord Takeda Shingen took the military fortification a few years after its completion.
This Romanesque castle in Bojnice may have been a wooden fort in 1113. Renaissance elements were added to Gothic castles in the 16th century as stone replaced wood.
After making Gondar the capital, Emperor Fasilides ordered the fortress-city's construction in 1636. Ethiopian emperors used to travel eating local food and sleeping in tents.
The towering fortress above Oman's Al-Batinah plain appears irregular. Although it was built around a large boulder at the foot of Mount Nakhal before the Islamic era, Nakhal Fort looks imperfect.