Rancho San Antonio Open Space Preserve has 2 named peaks. The highest is Black Mountain at 857 m. Other notable peaks include Ewing Hill.
There are 2 named mountains in Rancho San Antonio Open Space Preserve. The highest and the most prominent mountain is Black Mountain.

The highest peak in Rancho San Antonio Open Space Preserve is Black Mountain, at 857 m.
Notable peaks in Rancho San Antonio Open Space Preserve include Black Mountain and Ewing Hill.
