In 1762, at the initiative of Bishop Donato Maria Arcangeli, work was begun on the construction of a building to be used as seminary. The work, suspended ten years later due to the death of the bishop, was resumed by Grand Duke Peter Leopold of Lorraine, who decided to turn the building into a hospital, as replacement for the so-called "Old Hospital", established in 1703 at the order of Cosimo III on the premises of the pest-house and now become insufficient, situated just in front of the new construction. But even the new hospital, inaugurated in 1781, failed to satisfy the expectations since, with only about 50 beds available, it was poorly equipped to fulfil the needs of the Valdinievole area. Baldasseroni, a scholar of the time, also observed that "the old public Hospital being too small, it could not receive all of the ill except with severe inconvenience to them; a supply of fresh air, so necessary to the lungs of the sick, arrived only poorly [...] The reduction of a Building for a totally different purpose did not turn out as successfully as the architect had planned, he having thought of everything except the comfort of the patients, as the wards were very narrow, and unsuitable for use as a Hospital."

A Latin inscription above the entrance portal in the sober, elegant 18th-century facade recalls Grand Duke Peter Leopold, the promoter of the institution. Today the hospital built in the Lorraine era is flanked by modern, functional structures.