area include: Transportation Roads South Bend's location around the St. Joseph River has influenced the development of its streets. While city streets mainly follow a grid plan, road development also adapted to the river's path. South Bend is connected to state and national highway systems by State Roads 2, 23, and 933; U.S. Route 20 and 31; and Interstate 80 and 90, the Indiana Toll Road. The original routes of both the Lincoln Highway and the Dixie Highway also pass through South Bend. South Bend was also a town along the intrastate Michigan Road. Parts of Eddy Street, Sample Street, Chapin Avenue, Marion Street, and Madison Street form an incomplete loop around the downtown area; this was formerly referred to as "the innerbelt". Portions of State Roads 23 and 933 follow this route. For transportation around the South Bend metro area, there is the St. Joseph Valley Parkway, designated in places as US 20, US 31, and State Road 331, which bypasses South Bend to the south and west, and connects to Michigan to the north and the greater Elkhart area to the east. The Indiana Toll Road (Interstates 80 and 90) passes through northern South Bend. Intercity bus service South Bend is served by a single Greyhound station. The busses had operated out of the airport until 2019, when they relocated to a leased portion of the South Street Station. Transit Public transportation in South Bend is controlled by Transpo (South Bend Public Transportation Corporation). Transpo operates bus routes between stations located in South Bend and Mishawaka and provides services to the towns of Osceola and Roseland, from Monday through Saturday. In 2006, the Transpo fleet switched to biodiesel fuel. In 2015, Transpo added 16 new buses powered by compressed natural gas. The Transpo facility is also the first LEED Platinum transit facility in the country. The South Street Station serves as the main hub for most passengers, with multiple platforms and buses arriving frequently. Connections can be made to the Interurban Trolley in Mishawaka. Aviation South Bend serves as the transportation hub for Michiana. The South Bend International Airport lies off of U.S. 31 and the Indiana Toll Road in the northwest corner of South Bend. The airport connects South Bend to larger hubs including Atlanta, Charlotte, Chicago, Dallas, Las Vegas, Minneapolis, New York City, Orlando, Phoenix, Punta Gorda, Sarasota, and St. Petersburg, Florida. In April 2014, the