Rochester is served by three U.S. highways (U.S. 14, U.S. 52, and U.S. 63), and the southern edge of Rochester is skirted by Interstate Highway 90 and State Highway 30. Olmsted County Highway 22 is also a main highway in the city. A combination of skyways and subterranean walkways link most downtown buildings, which residents often use to avoid harsh winter weather conditions. Public bus transit is run by Rochester Public Transit. Its operations are carried out by First Transit. The city Rochester encourages biking through its numerous trails and to facilitate the biking program all the city buses have bike carriers for easy transportation of bikes.