Covering a surface area of approximately 8,500 m² within the medieval walls of the city of Prato, the former Campolmi textile mill is one of the most important examples of industrial architecture in the province of Prato.

The site now occupied by the Campolmi textile mill has been used for the production of textiles since the Middle Ages and, indeed, historic documents confirm the existence of a gualchiera (a building for fulling of cloth) on the same site as long ago as 1326. Located on the banks of the Gora del Fiume Romita (also known as the Gora delle Gualchiere), one of the artificial canals dug in the first half of the 13th century in order to enable use of the waters of the River Bisenzio for textile production, the building was later acquired by the church and transformed into a flour mill. Although the mill remained active throughout the 18th century, with the suppression of the monasteries it was entrusted to private management.

In March 1863, St. Clare’s Mill was bought by Vincenzo Campolmi, Luigi Cecconi and David Alphandery, established entrepreneurs from the Prato area, with a view to converting it into a water-powered textile factory. The resulting Campolmi textile mill soon gained a solid reputation for the quality of its textile finishings, while its owners eagerly ploughed their profits back into the local area by participating in many of the economic, commercial and socio-cultural initiatives which changed the face of the city of Prato. By the end of the 19th century, Campolmi textile mill had developed into a huge two-storey rectangular building built around a courtyard with a large basin for the collection of water and a 40 metre brick chimney in the centre.

Throughout the 20th century, the company developed to the point that the factory came to be considered a real and proper symbol of Prato’s textile industry. Furthermore, in addition to completing all the various processes involved in the manufacturing of textiles (e.g. fulling, dying, teaseling and rolling), the Campolmi factory was also involved in the training of new employees. Indeed, the factory was often referred to locally as the “training ship” as a result of the large number of textile technicians and entrepreneurs who learned the secrets of their trade there. The factory’s current size was achieved in the mid-20th century as a result of extensions such as the construction of the ogival-ceilinged dying works.

The company ceased trading in 1994.