Sadd Mu’awiyah, also knows as Sadd Al-Khanaq, is an old dam east of Medina in Wadi Al-Khanaq in Al Madinah Region in Saudi Arabia. The dam is a dam between mountains, and it is known for its small size but high engineering efficiency. It used local materials and integrated natural features for stability. Nearby, there is a smaller dam. Both, attributed to Umayyad Caliph Mu’awiyah via an inscription, are partially collapsed due to seismic events. The dam's construction showcases advanced ancient techniques and its importance in regional development. Its heritage value lies in its integration with the natural landscape and archaeological significance.