Following bequests and donations, between the end of the 13th century and the beginning of the 14th the hospital started to subdivide and organise its land in vast farm agencies called “grance”. Their presence included vast areas of the Val d’Orcia, the Val d’Arbia, of the Masse, the Crete and the Maremma, and which altogether was the largest land concentration of the Siennese state. For almost five centuries these were the foundations of the economic structure of Santa Maria until, in the 18th century, alienation was ordered.
Santa Maria della Scala had a very important role also in the cultural ambit, such as to be justly considered the “third artistic centre” of the city, together with the Palazzo Pubblico and the Cathedral. Works include the great fresco cycle with the Storie della Vergine (stories of the Virgin) realised on the external façade (unfortunately lost) by Simone Martini, pieces by Ambrogio and Pietro Lorenzetti (1335), the series of frescoes in the large hall of the Pellegrinaio, and the decoration of the vast apsidal zone of the church painted in the 18th century by Sebastiano Conca.