If you find it hard to enjoy cycling with cars and trucks flying by—not to mention the abundant traffic-control signals—the Rillito River Park Trail is for you. Part of the Rillito River linear park, which includes both banks of the river, the bike path is a two-lane asphalt road that winds along the north bank from Craycroft Road to Interstate 10. There are bridges over washes, and bypasses under north-south arterial streets, so you can ride across town nonstop. As for traffic, there will be nothing motorized, but there will be other users to whom cyclists must defer.
Runners up:
2. Saguaro National Park
3. Sabino Canyon
www.fs.fed.us/r3/coronado/forest/recreation/camping/sites/sabino.shtml