San Marcos is a city and the county seat of Hays County, Texas, United States. The city's limits extend into Caldwell and Guadalupe counties, as well. San Marcos is within the Austin–Round Rock–San Marcos metropolitan area and on the Interstate 35 corridor between Austin and San Antonio. Its population was 44,894 at the 2010 census and was an estimated 64,776 in 2019.Founded on the banks of the San Marcos River, the area is thought to be among the... Show more

source