The City of Dallas is the third-largest city in the state of Texas and the ninth-largest city in the United States. The city covers 385 square miles (997 km²) and is the county seat of Dallas County. As of July 1, 2006, U.S. Census estimates put Dallas at a population of 1,250,280. The city is the main cultural and economic center of the 12-county Dallas–Fort Worth–Arlington metropolitan area—at 6 million people, it is the fourth-largest metropolitan area in the United States. Dallas is listed as a gamma world city by the Loughborough University Globalization and World Cities Study Group & Network.
Dallas was founded in 1841 and formally incorporated as a city on 2 February 1856. The city is well known for its role in the petroleum industry, telecommunications, computer technology, banking, and transportation. It is the core of the largest inland metropolitan area in the United States and lacks any navigable link to the sea—Dallas's prominence despite this comes from its historical importance as a center for the oil and cotton industries, its position along numerous railroad lines, and its powerful industrial and financial tycoons.