The dog park, the state park and natural areas will remain open, however.
The city asks that guests observe CDC recommendations on social distancing and wear masks if unable to keep a distance of six feet.
People who violate the park closures will be fined up to $1,000 and possible arrest on charges of criminal trespass.
Visit their website for a full list of closures and openings.
San Marcos is around 165 miles west of Houston.
The video above is from a previous story.