Beaufort or Belfort Castle, known locally as Qal'at al-Shaqif (Arabic: قلعة الشقيف, romanized: Qalʾāt al-Shaqīf)[1] or Shaqif Arnun, is a Crusader fortress in Nabatieh Governorate, Southern Lebanon, about 1 kilometre (0.62 mi) to the south-south-east of the village of Arnoun.

Beaufort provides one of the few cases in which a medieval castle proved of military value and utility in modern warfare as well, as its late 20th-century history, especially during the 1982 Lebanon War, shows.

However, historians assume that the castle's commanding hilltop site made it a strategic position that was fortified before its capture by the Crusaders.

[4] Fulk, King of Jerusalem, captured the fortification of Qal'at al-Shaqif in 1139 and gave the site to the lords of Sidon.

Medieval historian Hugh Kennedy speculates that construction of the Crusader castle began soon after Fulk gave the site to the lords of Sidon.

[12] Kennedy highlights Deschamps' La Défense du Royaume de Jerusalem (1939) as a particularly important source in the study of Beaufort as "his descriptions and plans record a building which has probably been mutilated beyond recognition by recent military activity".

[4] The castle's strategic location, which affords a view of much of southern Lebanon and northern Israel, has caused it to be a focus for recent conflicts.

The Palestine Liberation Organization (PLO) held the castle from 1976 onwards, during the Lebanese Civil War and consequentially it was attacked dozens of times by Israeli forces in the space of five years.

The fighting caused damage to the castle, and in the aftermath the Israeli army adapted the site for their own use by building a large forward operations base adjacent to the fort's western wall.

As a result of the prior presence of the PLO and the fear of IEDs, Israeli soldiers manning the base were allowed to tour the upper floors of the fortress but prevented from accessing the lower parts.

After the Israeli withdrawal, attempts by local tourism services to restore the fort began, albeit in very slow progress and lack of funding.

[2][17] Divided into two wards, one occupying the lower ground to the east, the castle is roughly triangular in shape and measures about 150 by 100 metres (490 by 330 ft).