The convent of S. Maria is located near the hamlet of the same name, in open countryside, about one kilometre from Castiglione. It can be reached by proceeding initially in the direction of Desenzano and then turning right towards the hamlets of Astore and S. Maria. It is situated in a small valley between the green moraine hills and cultivated fields. The convent was built between the end of the 15th and the beginning of the 16th century by Father Girolamo Redini, founder of the Congregation of the Hermits of St Mary. The construction, financed by Francesco II Gonzaga (1466-1519), was built on the remains of an earlier building: it is certain that there was already a monastery on this site in the mid 12th century. The Friars Minor Observant, known as 'Zoccolanti', replaced the Redini Hermits in the 16th century when the latter's congregation was suppressed. During the Napoleonic era, all religious orders were suppressed and the building was sold and used for agricultural purposes, a use it partly retains today. A boundary wall encloses an area of about three hectares. The building is accessed through an entrance on the north side of the wall. The present building, which some assume to be just one of the three arms of the convent that existed in previous centuries, is characterised by a portico and an overhanging loggia with a double order of columns.
Also interesting is the basement, where a vaulted room and a fountain, of Etruscan manufacture, collecting spring water, can be seen. The fertile valley seems, in fact, to have been chosen for a settlement as early as Etruscan times and later by the Romans. The area delimited by the wall corresponds to the unit of measurement of the Roman centuriazione. St. Luigi's parents, Ferrante Gonzaga and Marta Tana, chose this place as their holiday resort after settling definitively in Castiglione in 1567 and gave themselves a wing of the convent. Apparently, St Louis himself often went there to pray. In 1584, he took refuge there after a sharp disagreement with his father over his desire to devote himself to religious life, in the Jesuit order. Chapel of St Louis. A plaque was placed in memory of this decisive moment in the Saint's life in the former friars' choir. The room was arranged as a chapel in honour of St. Louis in 1891, on the 3rd centenary of his death, by the then Bishop of Mantua, Monsignor GiuseppeSarto, the future Pope and Saint: St. Pius X. In 1605, the mother of St. Louis, Marta Tana, was buried in the monastery church, her remains were later transferred to Castiglione Cathedral in 1804 due to the demolition of the church after the removal of the Observant friars.