Manage state parks and historic sites to conserve natural and cultural resources, provide recreational and educational opportunities, and foster an understanding of the diversity of Texas' lands and heritage for all generations.Mustang Island State Park is 3,954 acres in Nueces County south of Port Aransas. With 5 miles of beach on the Gulf of Mexico the park is a great place to experience the outdoors as a family. Activities include camping, picnicking, fishing, swimming, hiking and mountain biking on 5 miles of open beach, sunbathing, surfing, kayaking and excellent birding, especially during spring and fall migrations. The park is open 365 days a year from 7am to 10pm. Entrance is free for anyone with a Texas State Parks Pass. Daily entrance is $5.00 for adults. Children 12 years old and under are free.