estado (state), northwestern Venezuela. Zulia is bounded north by the Gulf of Venezuela and west by Colombia. Except for two narrow corridors on the southeastern shore, the largest one lying between the states of Mérida and Trujillo, it surrounds Lake Maracaibo. The state is composed mainly of lowlands, hot and humid in the south and hot and arid in the north. The land rises in the west into the Sierra de Perijá and in the southeast into the Mérida Range. Formerly one of Venezuela's poorer states, dependent upon limited agricultural resources, Zulia was radically changed economically after the discovery of oil in 1914 and especially after World War II. The petroleum industry at Lake Maracaibo is located in one of the richest oil-producing regions of the world; it produces as much as two-thirds of Venezuela's oil. Refineries, pipelines, and thousands of oil derricks dot the landscape, and the population has increased greatly. The largest of the lakeside cities is the state capital, Maracaibo, the second largest city of Venezuela. Transportation to the oil centres is excellent. Area 24,400 square miles (63,100 square km). Pop. (2007 est.) 3,620,189.