The Hermitage Carceri/Eremo delle Carceri is in a forest gorge four kilometers above Assisi, on the slopes of Mount Subasio. "Carceri" means prison cells. Francesco dedicated himself to a life of preaching and missions, but throughout his life he would withdraw to the Carceri to pray and contemplate, as did other hermits before him. When he first came to the hermitage in 1205, the only building was a tiny twelfth-century oratory. Soon, other men followed Francesco, finding their own isolated caves nearby in which to pray. The oratory became known as Santa Maria delle Carceri after the small cells occupied by the friars. Around 1400, Saint Bernardino of Siena built a small friary, much of which can still be seen. In the centuries that followed, various buildings were added around St. Francis's cave and the original oratory, forming the sizeable complex that exists today. Visitors are welcome, and sculptures of Saint Francis and three other friars are on the grounds. The oak tree where San Francesco preached his sermon to the birds still exists today near a stone bridge.