Saturday’s ceremony comes after three years of renovation work and was attended by several western ambassadors and Egyptian officials.
Monk Damyanos, the monastery’s archbishop, says the library maintains the world’s second-largest collection of early codices and manuscripts, outnumbered only by the Vatican Library.
St. Catherine’s, founded in the 6th century, is one of the oldest Christian Orthodox monasteries, a UNESCO World Heritage site and one of South Sinai’s main tourist attractions.
It stands at the foot of Mount Sinai, also known as Jebel Musa or Mount Horeb, where Moses is said to have received the Ten Commandments. A small number of monks live and work there where they observe rituals unchanged for centuries.