Activities Abound in and around the San Marcos River! Squirrels are active by nature and at Pecan Park Riverside RV Park you can be as active or relaxed as you like! ON THE SAN MARCOS RIVER Fishing Drop in a line and see if you can reel in a smallmouth black bass, largemouth brown bass, catfish and perch! Floating The San Marcos River is the home of the Texas Water Safari, “The World’s Toughest Canoe Race. Swimming AWAY FROM THE WATER Bird (and Squirrel) Watching Hiking Cave Exploring Shopping And Much More!