Qasr al-Azraq (Arabic: قصر الأزرق‎‎, "Blue Fortress") is a large fortress located in present-day eastern Jordan. It is one of the desert castles, located on the outskirts of present-day Azraq, roughly 100 km (62 mi) east of Amman. Later, it would be used by the Ottoman armies during that empire's hegemony over the region. During the Arab Revolt, T.E. Lawrence based his operations here in 1917–18, an experience he wrote about in his book Seven Pillars of Wisdom. The connection to "Lawrence of Arabia" has been one of the castle's major draws for tourists.