The Biblioteca Estense (Estense Library), was the family library of the dukes of Este, in what is now Italy. Dating at least to 14th century, it was largely enriched during Ferrara's Renaissance, and finally established in Modena in the beginning of 17th century. It is one of the most important libraries in Italy. The library is located in the Palazzo del Musei, Largo Sant'Agostino 337.
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