Ninfa was a small but thriving medieval city founded near the Ninfa River springs. It was abandoned about 600 years ago and the remains have been turned into the garden by the Caetani family. Today the park is among the most beautiful in the world and is open on the first weekend of each month from April to October. Ninfa had important moments for its strategic position. Here Pope Alexander III was crowned. Its decline began with the Schismof the catholic church and Ninfa was destroyed, so much so that in the nineteenth century Gregorovius called it the "Pompeii of the Middle Ages." In 1921 Gelasio Caetani began cleaning up the area, with restoration of the ruins and the planting of some botanical species. Today Ninfa is also a bird sanctuary.