Saint Catherine's Monastery (Arabic: دير القدّيسة كاترين‎; Greek: Μονὴ τῆς Ἁγίας Αἰκατερίνης), officially "Sacred Monastery of the God-Trodden Mount Sinai" (Modern Greek: Ιερά Μονή του Θεοβαδίστου Όρους Σινά), lies on the Sinai Peninsula, at the mouth of a gorge at the foot of Mount Sinai, in the city of Saint Catherine, Egypt in the South Sinai Governorate. The monastery is controlled by the autonomous Church of Sinai, part of the wider Eastern Orthodox Church, and is a UNESCO World Heritage Site.

Built between 548 and 565, the monastery is one of the oldest working Christian monasteries in the world.[1][2] The site contains the world's oldest continually operating library, possessing many unique books including the Syriac Sinaiticus and, until 1859, the Codex Sinaiticus.[3][4] A small town with hotels and swimming pools, called Saint Katherine City, has grown around the monastery.