The valley or lowland relief includes four valleys, the most important of which is the Valle del Cibao, as it is the longest and most fertile, followed by the valleys of San Juan, Bonao and Villa Altagracia. The Hoya de Enriquillo is a depression produced by a caved-in tectonic fault and is noted for its location at 40 m below sea level, the lowest point of the Antilles.