This abbey is one of the most important buildings in Romanesque and Gothic style in the Marche. It was bacame a basilica in 1943 by Pope Pio XII. The pleasant town of San Lorenzo in Campo was named after the abbey which was founded in the early Middle Ages by Benedictine monks and which was built using materials from the destroyed nearby Roman town of Suasa Senonum. 

The abbey was dedicated to St. Lawrence, martyr in Rome. They were hard working monks who cultivated their land and also spent large part of the day praying. Ora et labora (Pray and work) was their motto.  The abbey, together with the wide surrounding area which also belonged to it and which was probably covered by woods, had a long history as an independent territory right up to the 19^th century. Among its various commendatory abbots was Giuliano Della Rovere, who later became Pope Julius II. It 'a majestic Romanesque-Gothic building with a nave and two aisles. The middle part is the oldest one, as it was built between the 7th and 9th centuries. Of great importance is the high altar for its rare and precious marbles. Under the high altar is a beautiful crypt excavated in 1940. The arches are supported by columns of grey granite coming from Egypt. Among the works of art worth mentioning are the two wooden crosses by the monk Fra Innocenzo da Petralia and Damiano d’Assisi), a canvas by Ramazzani from Arcevia (1535) representing “Madonna and Saints” and the canvas representing “St. Demetrius and St. Lawrence”.