Due to its close proximity to the Sacramento and San Francisco Bay Area regions, and because of its varied terrain, Knoxville's 17,700 acres attract many off-highway vehicle (OHV) enthusiasts each year. The landscape is characterized by steep and rolling hills with the vegetation varying from scattered hardwoods and grasses to dense chaparral brush. California gray pine and Macnab cypress are also dispersed throughout the area. Of particular note, are unusual plant communities unique to the area's serpentine barrens, which are closed to vehicles to protect the delicate vegetation.
From the town of Lower Lake go east on Morgan Valley Road 13 miles to the north entrance to Knoxville at Dunnigan Hill Road (this access not recommended for two-wheel drive vehicles beyond Round Mountain Road). Continue three miles further on Morgan Valley Road for the south entrance to Knoxville at the intersection with Devilhead Road (southeast of the McLaughlin Mine crushing plant). There are BLM signs at both entrances.
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