Atlanta is the capital and most populous city of the U.S. state of Georgia, with an estimated population of 529,110 in 2025, and it is uniquely known for having the densest urban tree coverage of any major U.S. city. Founded in the 1830s as a railroad terminus, the city was almost entirely burned to the ground in 1864 by Union General William T. Sherman during the Civil War, but it rapidly rebuilt into a national industrial center and the unofficial capital of the "New South." In the 1950s and 1960s, it became a pivotal hub for the civil rights movement, led by local figures such as Martin Luther King Jr., and today it remains a major transportation hub, with Hartsfield-Jackson International Airport holding the title of the world's busiest airport since 1998. With a nominal GDP of $473 billion in 2021, Atlanta's diverse economy spans sectors like aerospace, media, and technology, and it gained global prominence by hosting the 1996 Summer Olympics. In the 21st century, the city has undergone significant gentrification, particularly along the Atlanta Beltline rail trail, which has reshaped its demographics, politics, and culture.