Al-Ukhaydir, Tabuk Province

Al-Ukhaydir, also known as Haydar or Aqabat, is a historically significant fort located in the Tabuk Province of Saudi Arabia, situated southeast of the city of Tabuk. Built in 1531 by Turabay ibn Qaraja during the early Ottoman era, the structure served as a critical component of the defensive network protecting the Hajj caravan route between Damascus and the holy cities of Medina and Mecca. The site occupies a strategic midway point on this ancient trail, resting on sandy grounds within a deep gorge surrounded by rocky, lava-covered slopes. Its name, which translates from Arabic as "the small green place," likely references the sparse vegetation found in this otherwise arid landscape or links to local legends concerning the figure of al-Khadr, to whom a shrine was once dedicated within the fort's walls.

The location holds deep religious and historical resonance, having been first clearly documented in the 13th century by geographer Yaqut al-Hamawi, who noted that the Prophet Muhammad prayed there in 630 CE. A mosque was subsequently constructed at the exact spot of his prayer in the center of Wadi al-Ukhaydir. Despite its spiritual importance, the site was notorious for its harsh conditions; the 14th-century traveler Ibn Batuta described it as a "valley of hell" due to severe water shortages that once caused the deaths of many pilgrims. Today, the fort remains well-preserved, standing as a testament to the region's complex history of pilgrimage, trade, and military strategy under Ottoman rule. It continues to be a landmark of interest for those studying the architectural and cultural heritage of the Arabian Peninsula's desert routes.