This Crusader castle in Syria, fortified in the second half of the 12th century, reveals a form perfectly suited to its function -- in this case, defense against siege. The castle's surrounding curtain wall encloses a second ring of walls and towers built around a central court.

With this concentric layout, the knights could defend the outer perimeter from Muslim attackers and then fall back, if need be, toward the center. Because the inner walls are higher than the outer, the defenders could always dominate their enemy from a superior height.

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Crusaders took control of Krak des Chevaliers in 1144, building fortifications according to the latest principles of military science.
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The strategic castle overlooks the only gap in the coastal mountains
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To further thwart attackers, the Crusaders (known as Knights Hospitallers) built a great stone slope against the castle's slightly vulnerable south side. Eighty feet thick at the base, this masonry slope was so smooth that Lawrence of Arabia, who attempted to scale it barefoot in 1909, could make it only halfway up. (And that was without any knights bombarding him with stones and boiling oil.)

Other castle features that obstructed assailants include a moat, a drawbridge, and a steep passageway with four gates and an iron grating that slid down from the ceiling, closing the passageway completely. A series of zigzags forced invaders to move slowly, while strategic openings overhead allowed knights to shower their enemy with arrows, rocks, and flaming pitch.

Withstanding numerous Arab assaults during more than 100 years of occupation, the knights lived securely within the castle. The interior precincts have a fine Gothic balcony, a banqueting hall, a plain 12th-century Romanesque chapel, a stable that still has loops on the wall for tying up horses, and chambers that held kitchens and a five-year stock of provisions in case of siege.

The Crusaders were seriously shorthanded in the end, with only 200 knights in a castle that could hold 2,000. They finally surrendered the castle in 1271 after a brief siege by a sizable Muslim army. Although the Crusaders had maintained a 200-year presence in the Holy Land, within 20 years of the fall of Krak des Chevaliers, they had withdrawn from the Holy Land completely.

Here are links to dozens of other world-famous landmarks:

Abu Simbel, EgyptEiffel Tower, FranceThe Leaning Tower of Pisa, ItalyRoman and Georgian Bath, England
The Alhambra, SpainEllora Caves, IndiaMachu Picchu, PeruSt. Mark’s Basilica, Italy
Angkor Wat, CambodiaThe Forbidden City, ChinaMont-St.-Michel, FranceSt. Paul’s Cathedral, England
Arc de Triomphe, FranceThe Golden Pavilion, JapanNeuschwanstein Castle, GermanySt. Peter’s Basilica and the Sistine Chapel, Italy
Borobudur, IndonesiaThe Great Buddha, JapanPalace of Versailles, FranceShwedagon Pagoda, Myanmar
Chartres Cathedral, FranceThe Great Wall of China, ChinaThe Pantheon, ItalyStonehenge, England
Christ the Redeemer Statue, BrazilGuggenheim Museum, Bilbao, SpainThe Parthenon and the Acropolis, GreeceSydney Opera House, Australia
CN Tower, CanadaHagia Sophia, TurkeyPetra, JordanThe Taj Mahal, India
The Colosseum, ItalyHouses of Parliament, EnglandPompeii, ItalyThe Temple at Karnak, Egypt
The Dome of the Rock, IsraelThe Kaaba and Al-Haram Mosque, Saudi ArabiaPotala Palace, ChinaThe Terra-cotta Army, China
Easter Island Statues, ChileKrak des Chevaliers, SyriaThe Pyramids of Giza and the Great Sphinx, Egypt
Edinburgh Castle, ScotlandThe Kremlin and Red Square, RussiaPyramids of the Sun and Moon at Teotihuacán, Mexico


To learn more about other landmarks and vacation destinations, see:

ABOUT THE AUTHOR:

Jerry Camarillo Dunn, Jr., has worked with the National Geographic Society for more than 20 years, starting as a staff editor, writer, and columnist at Traveler magazine, then writing travel guides. His latest work is National Geographic Traveler: San Francisco. Dunn’s Smithsonian Guide to Historic America: The Rocky Mountain States has sold more than 100,000 copies. His travel pieces appear in newspapers such as the Chicago Tribune and The Boston Globe. Jerry Dunn's stories have won three Lowell Thomas Awards from the Society of American Travel Writers -- the highest honor in the field. He also wrote and hosted a pilot episode for a travel show produced by WGBH, Boston's public television station.