 ART provides a fixed-route bus service within Arlington County on sixteen routes and carries almost three million passengers annually.As part of the Arlington Initiative to Reduce Emission project (AIRE), the entire ART bus fleet runs on clean-burning Compressed Natural Gas in order to be environmentally friendly in Arlington County.ART’s purpose is to supplement the regional rail and bus service provided by the Washington Metropolitan Area Transit Authority (WMATA), providing local bus service, and connecting to neighborhoods, businesses, and departments within Arlington County.