The Town Library of Thun was established in 1785, its collection focus being on the 19th century (2,000 books). Some items, however, date back to the 15th century. Most of them were donated to the library. The only incunable in the collection is the account of the Turkish siege of Rhodes in 1480. It was published by Guillaume Caoursin, Vice Chancellor of the Order of St John, and contains numerous illustrations.
In 2002 the city of Thun donated the library's collection of rare books to the University Library Bern. For details on history, collection, development and conservation, see: "Old Town Library of Thun donation. Documentation on editing 2004-2013" in the appendix to the collections catalog below.