Tucson is a big city with only a little freeway. I-10 runs northwest-southeast along the west side of downtown, connecting Marana and Phoenix to the north with the southeast side and Vail. I-19 starts near downtown and heads south through Green Valley toward Nogales. Everything else moves on surface arterials: Speedway Boulevard, Grant Road, Broadway and 22nd Street run east-west, while Oracle Road, Campbell Avenue, Swan Road and Kolb Road run north-south, and the Aviation Parkway angles from downtown toward Davis-Monthan Air Force Base.
Without a crosstown freeway, a drive from the Foothills to the southwest side means a long string of traffic signals, and that stop-and-go is hard on brakes and cooling systems in summer. The washes that cross the city, including the Rillito, the Pantano and the Tanque Verde, have low-water crossings that flood fast during monsoon storms. Catalina Highway climbs Mount Lemmon in a long series of switchbacks, and Gates Pass Road twists through the Tucson Mountains on the west side, both demanding on brakes on the way down.
Tucson International Airport sits south of the city off Tucson Boulevard and Valencia Road, and its long-term lots are a common spot for a no-start. The Sun Link streetcar connects the University of Arizona, Fourth Avenue, downtown and the Mercado district, and Sun Tran buses cover the main corridors. Most neighborhoods are easy for a mechanic to reach, since the grid puts nearly every home a short drive from a major road. The exceptions are the hillside streets of the Foothills and the dirt roads at the desert edges, where clear directions help.