Auburn is a city in and the county seat of Placer County, California. Its population was 13,330 during the 2010 census. Auburn is known for its California Gold Rush history, and is registered as a California Historical Landmark.Auburn is part of Greater Sacramento and is home to the Auburn State Recreation Area. The park is the site of more sporting endurance events than any other place in the world, giving Auburn the undisputed and internationally acclaimed title of Endurance Capital of the World. Examples include the Western States Endurance Run; the Western States Trail Ride, also known as Tevis Cup Equestrian Ride; American River 50 Mile Endurance Run; American River 50 Mile Equestrian Ride; Way Too Cool 50 Kilometer Endurance Run; Auburn International Half-Ironman Triathlon; Auburn Century 100 Mile Bike Ride, Coolest 24 Hour Mountain Bike Race, Rio Del Lago 100 Mile Endurance Run, Sierra Nevada 50 Mile Endurance Run, and the Coolest Run: Ride & Tie.