Hotels, Restaurants and Religious Services (Yellow Page Search) Texas State University - San Marcos Area Airports Austin-Bergstrom International Airport , located 30 miles north of San Marcos, has approximately 240 daily flights and is served by American, Southwest, Delta, Frontier, Continental, United, America West, Northwest and Mexicana airlines. San Antonio International Airport , located 45 miles south of San Marcos, has approximately 260 domestic and international flights daily and is served by American, America West, Northwest, Southwest, Delta, Atlantic Southwest, Continental, United, Conair, Mexicana, Aeromar and Aerolitoral airlines. Rail Service Union Pacific Railroad serves San Marcos with an average of 20 trains per day, north and southbound. Union Pacific is one of the few U.S. rail lines that interchange cars with both Canadian and Mexican rail lines. Piggyback and switching services are available in nearby San Antonio. Amtrak provides four northbound and four southbound trains through San Marcos each week. For complete information overview, visit Amtrak Bus Lines Greyhound Bus Lines, Inc. , provides inter-city service to and from San Marcos. Bobcat Tram - Texas State University provides transportation for students and staff. CARTS – Capital Area Rural Transportation System , is a public fixed-route bus system, operating weekday hourly service and services every other hour on Saturdays.