The municipality of Los Cabos is at the southern end of the Baja California peninsula, where desert meets the sea and the Gulf of Mexico meets the Pacific Ocean. The basement rock underlying Los Cabos formed even earlier, approximately 115 million years ago. The municipality has an average altitude of forty meters above sea level. There are three main terrain types, mountain terrain, semi flat areas and flat areas. The mountains consist of the Sierra de la Laguna and the Sierra de San Lázaro, both formed of volcanic rock, covering about fifteen percent of the total territory with peaks between 400 and 1000 meters. The semi flat areas are located between the coast and the mountain ranges, mostly of sedimentary rock and account for sixty percent of the territory. The flat areas are along the coast, beaches and alluvial plains, which account for twenty five percent of the territory. As it is on the edge of the desert that covers most of the Baja California peninsula, it is one of the sunniest locations in the world, with an average of 320 days of sunshine per year. This pooling of brackish water has created an oasis in the surrounding Sarcocaule desert. The Río San José flows largely underground for from its origin in the
Sierra de la Laguna (Laguna Mountains), although its Miramonte River tributary adds almost an additional . Its tributaries flow down the eastern side of the sierra and include Santa Rosa, Santa Lázaro, San Miguel, San Ignacio (at La Palma), Caduaño, Miraflores and San Bernard. The river used to flow above ground until the beginning of the 20th century due to anthropogenic causes. For more than 250 years the Río San José has furnished drinking and irrigation water for the town of San Jose del Cabo, beginning as a source of fresh water for Spanish
galleons traveling back from the
Philippines. Over the sand bar from the estuary is a bay referred to by early Spanish explorers, including Sebastian Vizcaino, as the Bahía de San Bernabé or Bay of San Bernabé, and now as the Bay of San José del Cabo. The estuary is home to both native and migratory birds and aquatic species, 250 species of tropical birds alone. Vegetation varies mostly by altitude and soil type and how much moisture the area receives. However, almost all species are those adapted to desert and semi-desert zones. The highest elevations have pine forests. Wildlife is varied and includes mammals such as badgers, skunks, coyotes, foxes, pumas and other wild cats, deer, raccoons, rabbits, bats and various rodents. Bird species include quail, doves, cardinals, woodpeckers, swallows and marine species such as pelicans and seagulls. There are over 850 species of aquatic animals off the coast such as marlin,
sailfish,
swordfish, tuna, dorado and whales. Many species and subspecies of both plants and animals are endemic only to Baja California. ==History==