This sprawling expanse of protected land filled with stately saguaro cacti flanks Tucson to the east and west. Separated by the city, the eastern Rincon and western Tucson mountain ranges are about an hour drive apart. Both offer hiking, biking and horseback-riding trails, as well as loop roads for motorized expeditions. The Rincon district is the more ecologically diverse of the two areas, giving visitors the opportunity to experience low-lying desert and high-country forest in a single day. In the Tucson district, hundreds of petroglyphs left by ancient Native tribes can be spotted easily from the Signal Hill picnic site.