Cairo was once the location of an important Christian basilica and hence its name, Plebe Cairi. It was destroyed by Frederick I Barbarossa, who entrusted this part of land to Pavia in 1164. It appeared in 1250 on the list of estates under the domain of Pavia, as Cayre Vegium. In the 14th century, the estate belonged of the Beccaria family, whose branch changed the name into Beccaria della Pieve. The Pieve castle was destroyed in 1404 and the Beccaria della Pieve family was extinct in 1590, with Count Aureliano. The estate was purchased by Lorenzo Isimbardi, the master of Cairo, Marquis of Pieve del Cairo, in 1597. The Isimbardi family owned the place until 1797, when feudalism was abolished. The Perpetual Jubilee is an annual event marking the liberation of Cardinal Giovanni de Medici, who became Pope Leo X, by the people of Pieve from the hands of the French. Once elected pope, Leon X remembered this and released a Papal bull to the people of Pieve, absolving them of their sins. The church of St. Mary of Consolation was built in 1518. It has a nave, two aisles and no transepts, whereas its new sacristy has eighteenth century features. A large canvas depicts Leo X presenting the Perpetual Jubilee bull.