Heavenly Pass is a surprise. One doesn't expect much from desert scenery, but this is an amazing place. Marvelous geology and lots of wildlife, particularly birds. Large owls live here as well as vultures and red-tailed hawks. At sunset, the sky is filled with swallows.
The north end of the trail has a steepish grade and is loose on gravel.
The south section is steep and has some gravelly, washed-out areas, but there are also fun, tight switchbacks and great views across the valley.