austin_texas | populationdensity | 129665 (inhabitants per square kilometre) <tsp> austin_texas | areaofland | 6860 (square kilometres) <tsp> austin_texas | areatotal | 70395 (square kilometres) <tsp> austin_texas | areacode | 512 <sep> austin is the capital city of the us state of texas, as well as the seat and largest city of travis county, with portions extending into hays and williamson counties incorporated on december 27, 1839, it is the 10th-most-populous city in the united states, the fourth-most-populous city in texas, and the second-most-populous state capital city it has been one of the fastest growing large cities in the united states since 2010  downtown austin and downtown san antonio are approximately 80 miles (129 km) apart, and both fall along the interstate 35 corridor 
austin in texas has a population of 1296.65 people per square kilometer. a land area of 686 square kilometres. a total area of 703.95 square kilometres and the area code of austin (texas). is 512.no information