Tucked into John J. Stokes Park along the spring-fed San Marcos River in San Marcos, Texas, this beloved rope swing is a local rite of summer — a great place to cool off in the clear water and get in a little showing-off while you're at it. Just off Thompson Island, an ideal tree leans over the river with a sturdy plank ladder up the trunk, so you can climb as high as your nerve allows, grab the rope, and whip out over the water before letting go.

The San Marcos River is what makes the spot special. Fed by the powerful San Marcos Springs a couple of miles upstream, the river runs remarkably clear and a constant, refreshing 72°F year-round — cool on the hottest Texas day and swimmable in every season. The water is clean enough to see straight to the bottom, full of waving green plants and darting fish, and gentle enough here for a relaxed swim between swings.

John J. Stokes Park is a free city park, generally open daily from early morning until late evening, sitting downriver of the busier Rio Vista Park and its dam. That makes the rope swing a convenient but slightly tucked-away spot — easy to reach, yet a little removed from the biggest crowds. It's also a popular launch and landing area for the classic San Marcos pastime of floating the river by tube or kayak on a hot afternoon.

San Marcos is a genuine river town, and the San Marcos is one of the most ecologically special rivers in Texas — its crystal-clear, constant-temperature water supports rare and endangered species like the tiny fountain darter and Texas wild rice, found almost nowhere else on Earth. That's a big reason locals treat it with such care, and it's worth doing the same: avoid trampling the underwater plants, keep sunscreen and trash out of the water, and tread lightly so this living river stays as clear and healthy as it looks.

A few common-sense cautions, since this is an unsupervised natural swimming spot with no lifeguards. Always check the water depth and clear the landing zone before you swing or jump — river bottoms shift, and the San Marcos has been reshaped by floods over the years — and never assume it's as deep as last time. Keep a close eye on kids and weaker swimmers, be mindful of the current and other floaters, and know your own limits on that plank ladder.

Bring water shoes for the rocky spots, sun protection, and a dry bag for your phone, and pack out everything you bring to help keep this stretch of the river beautiful. Late spring through early fall is peak season, but thanks to those constant-temperature springs, the San Marcos rewards a dip almost any time of year — and few things beat the simple thrill of a good rope swing over cool, clear Texas spring water.