I read today about the Abuna Garima Gospels in Ethiopia. These are remarkable. They are held in an ancient monastery at 7000 feet above sea level.
The Monks always maintained that they were really ancient, but only with recent carbon dating have they been proven to be over 1600 years old; amongst of the oldest surviving gospels. Their bindings have recently been reset by a British Bookbinder. Their resistance against invasion, time and fire is a remarkable attribute.