It is a valley ranch located in San Mateo County inland from Half Moon Bay.

[2] A trail from the parking area consists of the old ranch road along Mills Creek.

After a mile, it passes a 1930s bungalow that serves as a park ranger residence.

The terrain is navigable for another mile above the Mills Barn and water tanks, until the trail fades into the dense growth of stinging nettles, poison oak, and coyote brush.

The foundation of the barn and other buildings, including an un-reinforced arched stone bridge, rely on Italian masonry techniques dating back to Roman times.