The town lies at the confluence of the Tronto River and the small river Castellano and is surrounded on three sides by mountains. Two natural parks border the town, one on the northwestern flank (Parco Nazionale dei Monti Sibillini) and the other on the southern (Parco Nazionale dei Monti della Laga). Ascoli has good rail connections to the Adriatic coast and the city of San Benedetto del Tronto, by highway to Porto d'Ascoli and by the Italian National Road 4 Salaria to Rome.