Standing proudly at the top of a hill, Colle della Guardia, this is the most important sanctuary in the civil and religious history of Bologna. You get to the church by climbing up Via di S. Luca, flanked by a long portico almost 4 km long, lined with chapels containing the Mysteries of the Rosary. The church has an elliptical plan, and the current arrangement is the work of Carlo Francesco Dotti (1723-57). Inside there are noteworthy paintings by Guido Reni and Guercino, but the real focus of popular devotion is the venerated icon of the Virgin Mary, which traditionally is attributed to Luke the Evangelist but is in fact a Byzantine work dating from the 12th century.