Czestochowa is located in the northern portion of Silesia and is the largest city in the region. It is a popular Catholic pilgrimage site, home to the Pauline monastery called Jasna Gora. The 14th-century monastery hosts such sacred religious artifacts as the painting of the Black Madonna, believed to have been created by St. Luke. The painting has been credited with protecting the monastery from a siege by the Swedish, and has been canonically crowned with a tiara of thorns three times, most recently at the order of the first Polish-born pope, John Paul II. Millions of pilgrims visit Jasna Gora to catch a glimpse of the Black Madonna each year, many of whom arrive on foot in the months of August and September.