Portland Mine Road Professional Review and Guide
"The Portland Mine Road is one of a number of designated vehicle access trails within the Lake Mead Recreation Area. The long trail leaves from US 93, 3 miles south of the Pierce Ferry Road. Initially, it follows the wide, graded dirt Cottonwood Road that leads to several subdivisions. The turn is well marked from US 93. After 8.1 miles, the trail turns off onto an ungraded, smaller trail. The trail leads down to Lost Cabin Wash; there is a well at the head of the wash. You will have the best chance of finding a shady campsite along this section of the trail as it passes through stands of juniper trees, Mohave yucca, and creosote bush.
Special Attractions: Winding trail in the Black Mountains; Access to Lake Mead National Recreation Area; Wild burros and bighorn sheep; Views of Lake Mohave and the Newberry Mountains. High-clearance 4WDs are recommended, though most stock SUVs are acceptable. Expect a rough road surface with rocks larger than 6 inches, but there will be a reasonable driving line available. Patches of mud are possible but can be readily negotiated; sand may be deep and require lower tire pressures. There may be stream crossings up to 12 inches deep, substantial sections of single-lane shelf road, moderate grades, and sections of moderately loose road surface."