San Marcos is located south of Austin and north of San Antonio in Texas. Most of the activities in San Marcos are spread out, and with the exception of student transportation, the public system is not convenient for most travel.
Likely, you will be traveling from one of those two cities, where rental cars are readily available at both the airport and city locations.
A vehicle is the best way to travel to San Marcos. We are right on I-H 35. Major airports are in Austin, 30 miles away, and San Antonio, 45 miles away.
Again, a car is the best way to get around San Marcos as most sights and restaurants are spread out. It's easy though to park and walk around downtown.
The closest airport to San Marcos is located in Austin and is a 45 minute drive or so from town. Austin is served by most of the main US carriers, and its airport code is AUS.