Shortly after the Spanish conquered the Incas, Franciscan friars began converting the indigenous people to Catholicism and building a massive church and monastery. Initial construction of Iglesia y Monasterio de San Francisco lasted 150 years and ended in 1680. The 8.7 acre complex continued to evolve into 13 cloisters and three churches. Inside are over 3,500 pieces of religious art. Among the interesting nuances are frequent images of the sun. These were created to help the Incas transition from worshiping their sun god to Christianity. Guided tours of Museo Franciscano and the monastery are fascinating. The Baroque complex with twin bell towers defines the western perimeter of Plaza de San Francisco.