Southern Careers Institute’s Campus of Harlingen: You’ll Leave With the Hands-On Training and Certifications You Need to Compete in Harlingen, Texas! Southern Careers Institute in Harlingen, Texas can be found in Cameron County. Located in the heart of the Rio Grande Valley, this South Texas campus is the Valley’s choice for career training. With a supportive and caring learning environment, SCI offers the kind of training Valley residents are looking for. Close to everything, this campus is perfectly located in Harlingen, Texas.