The history of papermaking in the Paper Mill Valley dates back to the Middle Ages and was naturally favoured by the presence of the River Toscolano. Even if the first document recording the presence of paper mills along the Valley and the use of the water of the River through a system of channels is documented already back in the end of the 13th Century, the first reliable document about the existence of a paper mill along the river dates back to 1381, 17th October. 15th Century documents refer to paper mills in all the main site of the Valley along the River Toscolano from Promontorio up to Camerate. By the end of the 15th Century the demands for printing paper made a huge difference in papermaking and between the 15th and the 16th Century the Valley with its blooming  industrial agglomeration became the leading paper production centre of the Venetian Republic. Only in the year 1630 when the plague claimed many victims the entire paper production came to an abrupt end. Between the end of the 17th Century and the beginning of the 18th Century closed or abandoned paper mills were ready to start up again by families of brave paper merchants and the production became even powerful than before. In 1797 the fall of the Venetian Republic made the decline of papermaking in the Valley unavoidable. Over the 19th Century only very few businessmen knew how to be in step with the times, bringing in new machineries by centralising the paper production in Maina and Luseti. In this last important change of methods in papermaking the brothers Maffizzoli played an important role by moving most of the Valley paper production to the Lake. In 1906 they built a brand new paper factory near the Lake and the paper mills in the Valley ceased progressively their activities. The year 1962 marks the end of papermaking in the Valley, when the paper mill in Maina inferiore ceased its secular production.