2.0 hr
From the end of the Nortonville Trail, near the park boundary, stay right at the junction with the Coal Canyon Trail. The ascent starts immediately past the Black Diamond Shaft mining site, steeply at times, to the junction with the paved Black Diamond Way. Only a short break as this road gets steeper as it passes the Cumberland Trail on the right. When the communication tower comes into view, the paved section ends at the gate and the dirt trail branches to the left at the high point of the loop. Most of the descent is smooth fire road with nice views to the Delta. The trail drops into Manhattan Canyon where there's some loose sand from mining operations and a short ascent out before reaching the junction with the Nortonville Trail.