town is served by U.S. Highways 30 and 69 and Interstate 35. Ames is the only town in Iowa with a population of greater than 50,000 that does not have a state highway serving it. , Ames currently has three roundabouts constructed on University Avenue/530th Avenue. The first is at the intersection of Airport Road (Oakwood Rd.) and University Avenue, the second at the intersection of Cottonwood Road and 530th Avenue and the third at Collaboration Place and 530th Avenue. Ames was serviced by the Fort Dodge, Des Moines and Southern Railroad via a branch from Kelley to Iowa State and to downtown Ames. The tracks were removed in the 1960s. The Chicago and North Western Transportation Company twin mainline runs east and west bisecting the town and running just south of the downtown business district. The C&NW used to operate a branch to Des Moines. This line was removed in the 1980s when the Spine Line through the nearby city of Nevada was purchased from the Rock Island Railroad after its bankruptcy. The Union Pacific, successor to the C&NW, still runs 60–70 trains a day through Ames on twin mainlines, which leads to some traffic delays. There is also a branch to Eagle Grove that leaves Ames to the north. The Union Pacific maintains a small yard called Ames Yard east of Ames between Ames and Nevada. Ames has been testing automatic train horns at several of its crossings. These directional horns which are focused down the streets are activated when the crossing signals turn on and are shut off after the train crosses the crossing. This system cancels out the need for the trains to blow their horns. Train noise had been a problem in the residential areas to the west and northwest of downtown. Ames Municipal Airport is located southeast of the city. The current (and only) fixed-base operator is Central Iowa Air Service. The airport has two runways – 01/19, which is , and 13/31, which is . The City of Ames offers a transit system throughout town, called CyRide, that is funded jointly by Iowa State University, the ISU Government of the Student Body, and the City of Ames. Rider fares are free for children under five, while students pay a set cost as part of their tuition. In addition to local transit, Ames is served by intercity buses from Jefferson Lines, which stop at