Austin is the capital city of the U.S. 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 11th-most-populous city in the United States, the fourth-most-populous city in Texas, the second-most-populous state capital city, and the most populous state capital that is not also the most populous city in its state. It has been one of the fastest growing large cities in the United States since 2010. Downtown Austin and Downtown San Antonio are approximately apart, and both fall along the Interstate 35 corridor. Some observers believe that the two regions may some day form a new "metroplex" similar to Dallas and Fort Worth. Austin is the southernmost state capital in the contiguous United States and is considered a "Beta −" global city as categorized by the Globalization and World Cities Research Network. As of 2021, Austin had an estimated population of 964,177, up from 961,855 at the 2020 census. The city is the cultural and economic center of the metropolitan statistical area, which had an estimated population of 2,295,303 , a roughly 84% increase from the year 2000. Located in within the greater Texas Hill Country, it is home to numerous lakes, rivers, and waterways, including Lady Bird Lake and Lake Travis on the Colorado River, Barton Springs, McKinney Falls, and Lake Walter E. Long. Residents of Austin are known as Austinites. They include a diverse mix of government employees, college students, musicians, high-tech workers, digital marketers, and blue-collar workers. The city's official slogan promotes Austin as "The Live Music Capital of the World", a reference to the city's many musicians and live music venues, as well as the long-running PBS TV concert series Austin City Limits. The city also adopted "Silicon Hills" as a nickname in the 1990s due to a rapid influx of technology and development companies. In recent years, some Austinites have adopted the unofficial slogan "Keep Austin Weird", which refers to the desire to protect small, unique, and local businesses from being overrun by large corporations. Since the late 19th century, Austin has also been known as the "City of the Violet Crown", because of the colorful glow of light across the hills just after sunset. In 1987, Austin originated and remains the site for South by Southwest (stylized as SXSW and colloquially referred to