Bats eat insects that might damage old books. At the heart of the University of Coimbra, one of the oldest educational institutions in Europe, is the Joanina Library, a veritable treasure trove of knowledge and baroque architecture.

This unique library is not only an impressive place with its sumptuous design, but also with an unusual method of protecting the books: a colony of bats has been living inside the library for over two centuries!

At night, the bats emerge from the massive carved wooden shelves and begin to fly among the old books, feeding on insects that might damage the fragile pages of the historic volumes.

These little book guardians play an essential role in preserving valuable collections by naturally eliminating pests without the use of chemicals that could harm sensitive materials.

To protect the library’s wooden furniture and surfaces from bat droppings, staff cover the reading tables with special leather at the end of each day. In the morning, the library is carefully cleaned and life goes on in this sanctuary of learning.

The Joanina Library houses approximately 60,000 volumes, including rare manuscripts, books from the 17th-18th centuries and works of inestimable value.

Thanks to bats, these literary treasures are preserved in excellent condition, and this unusual collaboration between man and nature continues to fascinate visitors from around the world.

So…if you ever get to Coimbra, don’t miss the chance to see this unique library with your own eyes, where history, architecture and nature work together!