El Semidesierto Queretano (Querétaro Semidesert) is a wide strip that crosses the state from east to west, which is dry due to the blocking of moist air from the Gulf by the Sierra Madre Oriental. The area is found in the municipalities of Cadereyta de Montes, Colón, Peñamiller and Tolimán, with an area of 3,415.6km2 or 29% of the state. As it is near the mountain range, its topography is relatively rugged. Los Valles Centrales (Central Valleys) is in the center of the state, overlapping almost all of the area formed by the Trans-Mexican Volcanic Belt, with the exception of the north of the El Marqués municipality, which is in the Mesa del Centro. The continental divide runs through here marked by the Sierra Queretana, the El Macizo and El Zamoarano mountain chains. This area occupies the municipalities of Ezequiel Montes, El Marqués, Pedro Escobedo and San Juan del Río with an extension of 2,480.2kmw or 21.1% of the state. El Bajío Queretano is in the western part of the state, which is a low elevation area that extends into neighboring Guanajuato. This area covers 1,005.7km2 or 8.5% of the state, and contains low hills and small mountain chains that are part of the Trans Mexican Volcanic Belt. La Sierra Queretana (Querétaro Sierra Mountains) is in the extreme south of the state, and also part of the Trans-Mexican Volcanic Belt. It is mostly found in the municipalities of Amealco de Bonfil and Huimilpan, covering an area of 1,078.3 km or 9.2% of the state. The area has high peaks and plains that narrow into valleys and canyons. Some of the flat areas border the Lerma River.