Transportation oversees Ohio’s $2.1 billion annual transportation program. The department is responsible for designing, building and maintaining Ohio’s nearly 20,000 miles of state, U.S. and interstate highways. Ohio has the second largest inventory of bridges, the fourth largest interstate highway system and the tenth largest highway system in the nation. ODOT also helps coordinate and develop Ohio’s public transportation and aviation programs. These include 56 public transit systems and nearly 200 public airports.