The ruined Rocca (castle) of Pierle was the site of the torture and murder of 60 conspirators and rebels in 1327. In 1428, the Pierle valley acquired economic and legal independence from Cortona and a commune was established. The fortress was partly demolished in 1576 by Grand Duke Francesco I De Medici to prevent highwaymen and enemies from seeking shelter in the building and has been abandoned since then.