The Monti della Tolfa or "Tolfa Mountains" are a volcanic group in the Anti-Apennines of the northern part of the Lazio region of central Italy. They are bounded by the Tyrrhenian Sea coast to the west, by the Monti Sabatini to the east, and by the Monti Cimini and the Mignone river to the north. Tolfa and Allumiere are the principal towns.