Qasr al-Azraq, also known as the "Blue Fortress," is a historic castle located in eastern Jordan. Built in the early 4th century and later renovated in 1237 CE, this fortress played a strategic role due to its proximity to the Azraq oasis, the only water source in a vast desert region. Over the centuries, it was used by various civilizations, including the Romans, Umayyads, and Ottomans. T.E. Lawrence, famously known as Lawrence of Arabia, made the fortress his desert headquarters during the Arab Revolt in 1917-18. Today, visitors can explore this partially ruined fortress and learn about its rich history and connection to one of the most iconic figures in Arab history.