The town of Rovinj contains coastal areas with a number of small bays hidden within dense vegetation, open to naturists. Although the beaches are not specified as naturist, naturists frequent them. The interior is green and wooded, with small stone towns on hills, such as Motovun. On the other side of the river lies Motovun forest, an area of about 10 square kilometres in the valley of the river Mirna, of which 280 hectares (2.8 km2) are specially protected. This area differs not only from the nearby forests, but also from those of the entire surrounding karst region because of its wildlife, moist soil, and truffles (Tuber magnatum) that grow there. Since 1999, Motovun has hosted the international Motovun Film Festival for independent films from the U.S. and Europe. Grožnjan, another hill town, hosts a three-week jazz festival every July.