If you go from Sidon towards the south or more exactly towards Nabatieh, which is 23 kilometers far from Sidon, Arnun is seven kilometers ahead. There, upon a hill you reach Beaufort Castle or the Castle of Shqif Arnun. It is 710m high.
It overlooks the district of the Litani Valley. According to Ghelyoon of Tyre, the fortress was built by the Crusaders. Other scholars say that it dates back to a previous period, either the Roman or the Byzantine. The Arabs renovated and expanded it. The Crusaders added pillars to it so it became the most important citadel in Lebanon. The king of Jerusalem, Fulk (Foulques d’Anjou), took it from the ruler of Sidon in 1138. Saladin besieged it for two years until he occupied it in 1190. The Crusaders regained it in 1240 after signing a treaty with As-Salih Ismail, ruler of Damascus. The Templers gave it to the governor of Sidon in 1260. In 1268, the Mamluk Sultan, Az-Zahir Baybars captured it. It was forgotten until the 17th century A.D., when Fakhr al-Din restored and fortified it. But, the governor of Damascus, Hafez Pasha besieged and bombarded it. The General Directorate of Antiquities restored it during the 1970s. Again, it was hit by Israel in 1982. Despite its destruction, it preserved some architectural structures. There are still two towers near the corner of the southern wall which stands on the slope of the valley, and which is erected from carved stones that surround the rocky foundations of the fortress. The main eastern entrance leads to the uppermost part of the fortress. The southern part has an observation post. The inner part of the fortress is in ruins.