Both rivers come from the same source — the Edwards Aquifer — and both run a steady 72°F year-round. So why does it matter which one you tube? Because the experience is wildly different. Here's the honest, side-by-side comparison from people who run a property on one of them: Son's Blue River Camp on the San Marcos.
The Quick Answer
Comal River: shorter, more chutes, much more crowded, party-leaning, in-town.
San Marcos River (at Son's): longer, gentler, private, family-leaning, country.
If you're 22 and your group has matching tank tops, go to the Comal. If you have kids or you want to actually relax, drive east to the San Marcos.
Water Temperature
Tie. Both are spring-fed at the headwaters and run roughly 70–72°F all year. The Comal is technically a touch warmer in summer because it's so short, the San Marcos picks up sun further downstream. In a tube you cannot tell the difference.
Crowds
San Marcos at Son's wins by a mile. The Comal in July averages 3,000–5,000 tubers a day across the public outfitters. The Tube Chute is famously a 30-minute wait. The San Marcos at Son's runs through a private 8-acre property with capacity capped daily — it feels like a friend's ranch, not a theme park.
Float Length
Comal floats are 2–3 hours including the chute. San Marcos floats at Son's are roughly 90 minutes river-time per lap, but the wristband includes unlimited re-floats with shuttle. Most groups float twice in a day — second lap with snacks and a slower pace.
Vibe
Comal: bachelorette parties, college groups, can-jammers. Music is loud, people are loud, you are loud. Great if that's the trip you're planning.
San Marcos at Son's: families, multi-generational groups, friends who want a riverfront cabin. Quiet hours are real. Music is allowed but not loudspeaker territory.
Drive Time
From Austin: Comal 60 min, San Marcos at Son's 60 min. Tie. From San Antonio: Comal 35 min, San Marcos at Son's 50 min — Comal closer. From Houston: both about 3 hours. From Dallas: both about 3.5 hours.
Where to Stay
This is where the San Marcos pulls ahead. Comal lodging is hotels and Airbnbs in town — none of them on the river. San Marcos at Son's has riverfront log cabins, glamping cabins, and tent sites at the put-in. You wake up, walk out, you're floating.
Pricing
Comal outfitter tubes run $20–25 per person plus parking ($10–20). San Marcos at Son's is $29.99 unlimited with shuttle, parking included. If you float twice, Son's is cheaper. If you float once and leave, Comal is cheaper.
Kids
San Marcos wins. The Comal's tube chute is a 4-foot drop that scares some kids and isn't safe for little ones — most outfitters route them around. The San Marcos at Son's has no chute, gentle current, and shaded river beaches every few hundred yards for breaks.
Cooler Tubes & Glass
Both rivers ban glass. Both allow cooler tubes. The Comal Bandit-style chute can dump coolers in the rapid; the San Marcos has no chute so coolers stay in.
Cleanliness
The Comal is famously clean for a public tubing river — locals are passionate about Litter Patrol. But sheer volume means cans, cups, and lost goggles. The San Marcos at Son's, being private, gets daily property cleanups and feels pristine.
When to Choose Each
Pick the Comal if: you're young and want a party, you want walk-around bars in New Braunfels after, or you're doing a one-hour quick float.
Pick the San Marcos at Son's if: you have kids, you want to camp/cabin overnight, you hate crowds, or you want unlimited floats in one day.
FAQ
Can I do both in one weekend?
Yes. Float the Comal Saturday morning, drive 20 minutes east, sleep at Son's, float the San Marcos Sunday. Best of both.
Which is better in October?
San Marcos. Comal outfitters scale back; Son's runs floats year-round.
Are dogs allowed?
San Marcos at Son's: yes, on shore (no tubing). Comal: outfitter-dependent.
Tube the Quieter River
Same spring water, half the crowd, twenty minutes east of New Braunfels.
