Austin to San Antonio: Three Good Stops on I-35
Leaving from somewhere else? Change the start and see your stops right now — your first trip is free, no signup.
About 80 miles from downtown Austin to downtown San Antonio — mostly I-35 South, a straight drive through the Texas Hill Country with quick towns and big rivers that reward short detours. Here is where we get out: a spring-fed city river for a walk or a float in San Marcos, the historic Gruene district and its old dance hall in New Braunfels, and a surprisingly large limestone cavern complex a little north of San Antonio.
- 80 miles · central Texas
- 1 hr 20 min driving with clear roads
- I-35 S most of the way; short detours on Gruene Road and FM 3009
- Spring-fed rivers, German-era small towns, and limestone caverns
This is a short corridor drive — long enough that a stop or two makes the trip feel like a proper day out, short enough that you can do it in under two hours of total driving. The interstate itself is the fastest way, but the towns along it are where the worthwhile pauses are: San Marcos' clear spring-fed river, the small historic village of Gruene (part of New Braunfels) with a dance hall that actually matters, and the Natural Bridge Caverns complex tucked off the highway before San Antonio.
We like to think of it as three quick, different things that together show the corridor. San Marcos is water — a shallow, cold stream that comes out of the ground and invites walking, wading, or tubing. Gruene is food and music and a bit of old Texas that still leans hard on its German roots. The caverns are the geological surprise: a cool underground set of rooms and passageways with real speleothems and an easy visitor program. All three are easy to reach from I-35 and don't demand huge detours.
Stop 1 — San Marcos River and Downtown San Marcos
Mile 30 · right off I-35 · 45 minutes to 1.5 hours
About thirty miles out of Austin you will reach San Marcos, where the river is literally the town's center. The San Marcos River issues from springs at Spring Lake and the Meadows Center, and the water is clear and cold year round. There is a paved riverwalk and easy access points in and near downtown; this is the place to stretch legs on a flat, shady walk or to spend an hour floating if that's your thing.
For a quick pause: park near downtown, walk the riverfront toward Spring Lake and watch the people and university life. There are coffee shops and lunch spots a couple of blocks away. If you want something more active, the local outfitters run short tubing trips (drop-in / pick-up services) that are summer staples.
If you have an extra 2 hours: rent tubes from one of the outfitters on the river and float a gentle section; alternately visit the Meadows Center's spring area / Aquarena Springs for short guided glass-bottom-boat-type views of the headwaters if public programs are running.
Stop 2 — Gruene Historic District, New Braunfels
Mile 48 · about 5–10 minutes off I-35 at New Braunfels · 1 to 2 hours
Gruene (pronounced "Green") is the small historic riverside district now inside New Braunfels city limits, and it is the corridor's most characterful stop. The centerpiece is Gruene Hall, a wooden dance hall from the 19th century that still hosts live music several nights a week. The street is a short run of historic storefronts with a winery or two, restaurants, and outfitters for the nearby Guadalupe and Comal rivers.
This is where we plan a proper lunch: barbecue or Tex-Mex here is solid, and there are good riverside beer gardens in the afternoon. If you are traveling with a kid or someone who wants slow, it's a pleasant place to set up a short stroll and watch kayaks and tubers come through.
If you have an extra 3 hours: rent a tube or kayak on the Guadalupe/Comal and run a section, or time your trip to an early-evening show at Gruene Hall (tickets sell out on weekends).
Tell us where you are leaving from, when, and who is in the car — dog, toddler, EV, six-hour limit — and we will name the stops that actually fit. Your first trip is free, no card.
Stop 3 — Natural Bridge Caverns
Mile 62 · about 8 minutes off I-35 at exit 175 / FM 3009 · 45 minutes to 1.5 hours
Turn off I-35 at exit 175 and follow FM 3009 a few miles to the parking area for the Natural Bridge Caverns. For such a short interstate drive this is the one place that feels like an entirely different world: the cavern tours take you into limestone rooms with columns and draperies, and the temperature down there is a welcome change on a hot Texas afternoon.
The operator runs several tour types — the standard discovery tour is the quickest way to see the main rooms, while specialty or lantern tours take longer and can be worth it if you are into geology or spelunking history. Aboveground there is usually a small plaza with a gift shop and a café; families often combine the cavern tour with a short ropes course or gem-mining activity if those are open.
Why we put it last: it's close to San Antonio and works as a final leg-stretch before you arrive downtown. The caverns are also a cooler, calmer place late in the day when town temperatures are high, and the underground tour gives you a sense of scale and the hill-country geology that underpins this whole corridor.
If you have an extra 2 hours: book one of the longer guided tours (lantern or discovery-plus) or add the aboveground attractions. If you are into birding, the nearby Bracken area hosts big bat and bird colonies seasonally; check local notices before you go.
Arriving at San Antonio
Downtown San Antonio is compact and obvious once you pass the airport and Loop 1604; follow I-35 into the heart of the city and take the downtown exits for the River Walk / Alamo area. The San Antonio River Walk is the right first stop for most visitors — a short loop beside the water with restaurants and boat tours — and the Alamo sits a few blocks away on Alamo Plaza. Downtown has hotels, large-chain parking, and the visitor infrastructure you will want after a day on the road.
How we would time it
Leave Austin in mid-morning if you want to avoid the worst I-35 commuter traffic out of the city. A sample plan: depart downtown Austin at 9:00, reach San Marcos around 9:35 for a coffee and a 45-minute stroll along the spring-fed river, back on I-35 by 10:30 and into Gruene around 11:15 for lunch and a quick walk (1–1.5 hours). Leave Gruene by about 12:45, take the short drive to Natural Bridge Caverns and arrive around 1:30 for a cave tour that finishes mid-afternoon. From the caverns it is about 25–30 minutes into downtown San Antonio without heavy traffic, making for a relaxed late-afternoon arrival and check-in.
Booking the rest of it
Because the drive is short, the main things to book ahead are cave tour times on busy summer weekends and Gruene Hall tickets for evening shows. If you need a rental car for the corridor compare EconomyBookings and GetRentacar. San Antonio's hotels fill for Fiesta and major conventions well in advance, so if your dates overlap large events reserve early; otherwise downtown has a range of options and New Braunfels/Gruene has a handful of inns if you prefer to stay near the river.
One small but practical note: I-35 is a major freight and commuter artery, and construction or rush-hour slowdowns are common. If you are on a tight schedule allow extra time between stops — the corridor is short enough that a 20-minute delay on I-35 is painless, but it will make you choose which stop to shorten.
FAQ
Is the drive from Austin to San Antonio long? The interstate distance is about 80 miles and typically 1 hr 20 min of driving without stops. Allow extra time for rush-hour congestion.
Can you tube the San Marcos or Guadalupe Rivers on this route? Yes. San Marcos and the Guadalupe/Comal around New Braunfels/Gruene both have outfitters offering tubing and kayaking; seasonality and safety notices apply — summer is busiest.
How long does a Natural Bridge Caverns tour take? The standard discovery tour is usually under an hour; specialty tours run longer. Add time for parking, the visitor area, and any aboveground activities.
Is Gruene Hall worth visiting? For many travelers yes — it is one of the oldest continuously operating dance halls in Texas and still hosts live music. Even if you don't attend a show the historic street and riverfront make for a pleasant lunch stop.
What should I watch out for on I-35? Construction and commuter congestion, especially around Austin and through San Marcos/New Braunfels during weekday mornings and late afternoons. Consider timing your drive mid-morning or mid-afternoon to avoid peak congestion.
The three stops on a map
Stops in driving order. Map data © OpenStreetMap contributors.
How far is Austin to San Antonio and how long does it take?
About 80 miles and roughly 1 hr 20 min of driving on I-35 with light traffic; plan on 2 to 3 hours total with a couple of short stops.
What are the best stops between Austin and San Antonio?
San Marcos for the spring-fed river and tubing; Gruene in New Braunfels for Gruene Hall, shops and riverside lunch; and Natural Bridge Caverns for a cool underground tour.
Can you tube the rivers along the way?
Yes. Outfitters on the San Marcos River and on the Guadalupe/Comal at New Braunfels / Gruene rent tubes and kayaks; summer is busy so reserve or arrive early.
Is Natural Bridge Caverns open year-round?
The caverns generally operate year-round with multiple tour options, but specialty events or seasonal activities vary — check for tour times if you are on a tight schedule.
Where should I stop for food on this drive?
San Marcos has cafes and college-town options; Gruene is our lunch pick for barbecue, Tex‑Mex and beer gardens; downtown San Antonio has the widest choice after arrival.
Now let us do this for your drive
Every stop above is one we would take ourselves — but it is our day, not yours. Change the departure time, the driving limit, the dog in the back seat, the EV that needs a charger every 200 miles, and the right stops change with it. That is the whole thing we built: you tell us the trip, we name the three good stops, with the drive math already done.
Leaving from somewhere else? Change the start and see your stops right now — your first trip is free, no signup.
Seeing your stops is free. The full plan — clock times, weather, what is open when you arrive — is free for your first trip, then 99¢ for three trips or $2.99 a month. If you just want to browse, we have stop-by-stop pages for thousands of routes.
We write one new drive a week — three real towns, the drive math, what we would skip. Leave an email and we will send them as they go up. No more than one a week, unsubscribe in a click.
Updated 2026-10-21. Some links on this page are affiliate links. If you book through one, we may earn a small commission at no extra cost to you. It never changes which stops we pick — no business on this page paid to be here.