City Data San Marcos, Texas (TX 78656) profile: population, maps ... city-data.com http://www.city-data.com/city/San-Marcos-Texas.html San Marcos, Texas (TX 78656) profile: population, maps ... San Marcos, Texas (TX 78656) profile: population, maps ... San Marcos, Texas (TX 78656) profile: population, maps ... San Marcos, Texas (TX 78656) profile: population, maps ... San Marcos, Texas (TX 78656) profile: population, maps ... San Marcos