In the 1920s, an urgent call went out to the literati across the Middle East from Arab leaders in Jerusalem: Send us your books so that we may protect them for generations in the newly minted Al-Aqsa mosque library. Decades later — after riots and the wear of time — many of those centuries-old manuscripts are in a state of decay, left in tatters with shards of paper crumbled off their pages. Now, religious authorities are restoring and digitizing the books, many of them written by hand.

They hope to make them available online to scholars and researchers who are unable to travel to Jerusalem. Hamed Abu Teir, the library’s manager, called the manuscripts a “treasure and trust.”

The Al-Aqsa mosque, Islam’s third holiest site, is located on ground zero in the territorial and religious conflict between Israel and its Arab neighbors. Among its collection of 130,000 books are 4,000 manuscripts, mainly donations from the private collections of Jerusalem families. UNESCO, which is providing assistance for the restoration, said the library contains “one of the world’s most important collections of Islamic manuscripts.” Most of the texts are religious, but other subjects include geography, astronomy and medicine. Some of the pages contain personal letters about travel in the 18th century. In the six years since the project began, Radwan Amro and his 10-person team have restored 200 manuscripts — painstakingly treating every page — as well as maps, Ottoman population and trade registers and handwritten documents from the Mamluk period of the 13th to 16th centuries. Amro joked that it could take “hundreds of years” to finish the project. But he hopes to have the manuscripts online by year’s end.