The Basilica di San Petronio is a prominent church located in the heart of Bologna, Italy. Construction began in 1390, and it is dedicated to the city's patron saint, San Petronio. The basilica is known for its impressive Gothic architecture and is one of the largest churches in the world, although it was never fully completed. Inside, the basilica features stunning artworks, including frescoes and altarpieces by renowned artists. One of its notable elements is the Meridian Line, a solar calendar that helps track the passage of time. The basilica stands as a significant cultural and historical landmark in Bologna.