Saguaro National Park: Tucson Mountain District

The western district was added to the monument by President Kennedy in 1961, at the urging of Tucson residents and Interior Secretary Stewart Udall. It is the smaller half of the park, at 25,391 acres, and lower, with its high point on Wasson Peak at 4,687 feet. What it lacks in height it makes up for in sheer numbers: the park describes a higher density of saguaros here than in the east, in a younger forest.

The Bajada Loop Drive is the classic way in. This graded dirt road, which the park's current driving page puts at 6 miles and older pages at 5, has pullouts, picnic areas and trailheads, and it does not need high clearance. It begins at Hohokam Road, about 1.5 miles west of the Red Hills Visitor Center. The rule on oversize vehicles is the same as on the east side, and there is no RV parking on the loop, though RVs can park at this visitor center. The loop is closed to vehicles from dusk to dawn.

Signal Hill is the stop not to miss. Its picnic area is the access point for a hillside of petroglyphs. Most rock art in the park appears to date from the Hohokam period, when farmers and hunters lived in southern Arizona's valleys from about A.D. 300 to 1450, and designs include spirals, geometric forms, people and animals such as mountain sheep. No one is sure what they meant. They might have marked boundaries, recorded events or tracked the calendar. Do not touch them, because oils from your skin can damage the images.

For a short walk, the Desert Discovery Trail is the accessible choice. Longer routes include the Hugh Norris and King Canyon trails, and the park has 43 miles of trail on this side. Bicycles are limited to the loop, paved roads and two multi-use trails, the Belmont and the Golden Gate. Golden Gate Road was closed to vehicles for good between the Sendero Esperanza trailhead and Picture Rocks Road and is now one of those trails. There is no camping in this district.

The Red Hills Visitor Center is a mile north of the junction of Kinney and Mile Wide roads, and has water on the patio and public Wi-Fi. Elsewhere in the park cell coverage is patchy. Sunset is worth staying for, since the Tucson Mountains form the city's western skyline, but check closing times before you set off. The Arizona-Sonora Desert Museum is just a mile down Kinney Road, so the two fit well into a single day. Wildflowers usually peak in March.