Al-Samallagi Ancient Dam

Al-Samallagi Ancient Dam is one of the archaeological sites in Taif Governorate in Makkah Al-Mukarramah Province in the Kingdom of Saudi Arabia. It is a historical dam that was likely built during the reign of Muawiya Ibn Abi Sufyan. It was given this name in reference to “al-Samlaq,” which means flat land. It is called Thumalah Dam and Bani Hilal Dam. The dam is full of Kufic Arabic writings inscribed on its stones, and it represents an advanced architectural model.

Al-Samallagi Ancient Dam is located in Wadi Thumalah, about thirty km southwest of Taif, between two mountains in a valley filled with sidr and acacia trees at the front end of the dam. At the back, there are farms for grapes, alfalfa, tomatoes, and various vegetables. The length of the dam is 212 m, the height is twenty-five m, and the width at the top is ten m, while the storage capacity is estimated at about half a million m.

Al-Samallagi Ancient Dam is a double-walled dam with a stepped facade, which contributes to redirecting and transporting rainwater upon impact with the front dam wall. Its walls were built with massive stones, with rubble interlaid between them. The stones of the back facade of the dam were larger than those in the front facade.

The northwestern part of the dam was built on a substantial hill between a rocky outcrop that marks the narrowest point in the valley. Evidence of the dam's erosion-induced fracture is visible, with copious amounts of sediment having gathered in front of al-Samallagi Dam's facade. The facade and upper portions are encased in a layer of mortar. To the west of the dam lie the remnants of the historical Manifa village, alongside two watchtowers designed for surveillance and protection. Behind the dam, there is a water channel used for diverting water to one of the wells, located approximately forty m away. This channel is used for irrigating the lands situated behind the dam.

There are two written inscriptions next to al-Samallagi Ancient Dam. The first inscription includes illegible writing, the text of which states that the dam was built during the reign of Muawiya Ibn Abi Sufyan. The second inscription includes three lines that transliterate: "Ana Dinar, babi wa aseereh, and b'ameer".

Taif Governorate is home to approximately seventy dams, each bearing inscriptions, monuments, and religious dates that have intertwined with human existence since ancient times. Among them is al-Uhaymar Dam, situated on al-Uhaymar trail, south of the governorate. Saysad Dam, located to the southeast of Taif, is distinct in its construction from other dams, having been built upon a natural water reservoir using rectangular stone blocks arranged meticulously. Moreover, Thalabah Dam, positioned about seven km from Taif in a narrow valley, was built using square stone blocks and its parallel walls were filled with pebbles and small rocks.

These dams form architectural paintings in the heart of the valleys and mountains, bringing together the harmonious views that inhabited the place for successive periods of time.