Riserva naturale Cornate e Fosini, Regional nature reserve in Radicondoli, Italy

Riserva naturale Cornate e Fosini is a protected area of 879 hectares in the provinces of Siena and Grosseto, established in 1996. Its limestone massif includes the Cornate di Gerfalco, which reach 1,060 metres, with Posidonia marl and sandstone outcrops. Mixed deciduous woods cover the northern slopes, while the southern slopes carry scrub and abandoned pastures.

The reserve was established in 1996 and covers 879 hectares, 409 of them in the province of Grosseto, within the municipalities of Montieri and Radicondoli. In 2005 the area was recognised as a Site of Community Importance for the rare and endemic plants of its limestone grasslands. Fosini Castle stands on the overhanging limestone walls above the reserve.

The reserve lies in the municipalities of Montieri (Grosseto) and Radicondoli (Siena), and its name joins the Cornate di Gerfalco, a limestone peak of 1,060 m, with the Castello di Fosini, perched on overhanging limestone walls. The castle is the landmark visitors see from the trails, and the surrounding cliffs and meadows are the reason the area was recognised for its rare and endemic plants.

From the village of Radicondoli, visitors can access the area via multiple hiking trails that lead through different habitats and geological features. Bringing sturdy hiking shoes is advisable given the varied terrain and elevation changes.

The castle's limestone crags host the wallcreeper (Tichodroma muraria) alongside raptors such as the short-toed eagle, a confirmed breeder in the reserve, and the lanner falcon, a possible breeder in the site or nearby areas. The cliffs are a key conservation target of the reserve.