The church of San Francesco d'Assisi in Grosseto was originally dedicated to San Fortunato. In the 13th century it was given by the Benedictines to the Franciscans together with the adjacent cloister.
The church, one of the most important in the city, has a sober façade with a portal characterized by a frescoed lunette, which in turn is surmounted and protected by a wooden tabernacle, above which there is a rose window.
The interior consists of a single nave in Gothic-Franciscan style with a gable roof and houses various works of art, among which the famous Crucifix on a panel stands out, created towards the end of the 13th century by Duccio di Boninsegna. Inside there are also frescoes dating from between the 14th and 17th centuries.
From the end of the 16th century, the construction of the Medici Walls - which form a promenade around the city of Grosseto - led to a reduction in the size of the Franciscan monastery attached to the church and a consequent reorganization of its spaces.
The most important intervention in the building was the addition of the 17th-century chapel dedicated to Saint Anthony of Padua, with frescoes by Francesco Nasini, while in 1623 the bell tower was rebuilt, destroyed by lightning in 1917 and later rebuilt in style.