A new national study by The Media Audit shows that Texans are among some of the heaviest users of outdoor advertising in the U.S. According to the 87-market survey, Houston-Galveston and Riverside-San Bernardino (California) took the top two spots in a survey of the nation's top heavy outdoor users, followed by Austin, San Antonio, and Dallas-Ft. Worth, Texas. According to the survey, heavy outdoor users are defined as having driven more than 200 miles in a typical week.