Feb 16 UPDATE: Reports are the route described below has been fenced off. Once we get a confirmation on the best route we'll post it.
We have a quick update on access to the petroglyph area for the next few months. Construction has officially begun on the paved road leading to the new visitor contact center. For the duration of the construction work vehicular access to the Sloan Canyon parking area will be cutoff. BLM is asking all visitors wishing to visit Sloan Canyon from the north to park at Adventura Park, located on Via Firenze just south of Bicentennial Parkway. From the park walk south on Via Firenze to where it meets Democracy Drive. Proceed west along the new road then south at the BLM Sloan Canyon sign to the unpaved parking area. The trailhead is located at the parking lot. A larger more detailed view of this map is available on Google Maps.