Tulsa, located in the northeastern corner of Oklahoma, lies between the edge of the Great Plains and the foot of the Ozark Mountains in a generally forested region of rolling hills. The city serves as the gateway to "Green Country," a popular and officially designated name for northeast Oklahoma. The nickname is due to the region's dense green vegetation and relatively high amount of hills and lakes compared to that of Central and Western Oklahoma (which have geography similar to "Great Plainsthe Great Plains" region of the U.S.). Northeastern Oklahoma contains more than half of the state's registered state parks and six of Oklahoma's 11 ecosystems, more than a dozen major reservoirs, as well as the state's most diversified agricultural economy and outdoor sports and recreation industry. The city is split by the prominent Arkansas River. The Arkansas River flows in a wide, sandy-bottomed channel. Its flow in the Tulsa area is controlled by upstream flood-control reservoirs and the width and depth of water in the channel can vary widely throughout the year. Except in the most severe drought (as experienced in 2006) a low-water dam maintains a full channel in the area adjacent to downtown Tulsa. Tulsa is heavily wooded, with abundant parks and water areas. Several prominent hills with names such as "Shadow Mountain" and "Turkey Mountain" create varied terrain mostly in the southern portion of the city. The central and northern sections are generally flat to gently undulating, although the Osage Hills extension into the northwestern part of the city further varies the landscape. Tulsa's Geographic coordinate systemgeographic coordinates are (36.131294, -95.937332), with an elevation of 213 m (700 ft) above sea level. According to the United States Census Bureau, the city has a total area of 483.9 km sq (186.8 square miles). 473.1 km sq (182.6 mi sq) of it is land and 10.9 km sq (4.2 mi sq) of it (2.24%) is water. is the first of many developments planned or under construction along the Arkansas River in the Tulsa area. Source: http://en.wikipedia.org/wiki/Tulsa%2C_Oklahoma