The trails are mostly redwood forest duff, with some short sections of slick limestone near "The Top of the World" (the disc golf last hole). Trail maintenance is inconsistent, so watch for fallen limbs and trees. It's super easy to go fast on a straightaway then wash out in a sandy turn, so take it easy until you know the trails. If you crash, landings are mostly soft, though rocks, large trees and poison oak are hazards like anyplace else in Santa Cruz County. Small children and off leash dogs are very common in this park so keep your eyes open for them.
Directions: Most mountain bikers park at the lower trailhead in a dirt parking lot just north of where Market Street becomes Branciforte Drive. I usually ride my bike down Glen Canyon Rd from Scotts Valley, make a left on Branciforte (towards the Mystery Spot) and enter the ballfield area of Delaveaga.
Trails: The Redwood Loop and La Corona Trail are the main out and back trails used by mountain bikers. If you like pain, the Branciforte Trail has some steep, challenging sections. A couple of trails will take you to the golf course, and La Corona ends a the final hole of the disc golf course, so watch for people playing through. Unfortunately, as of this writing the city of Santa Cruz reorganized their website and the park trail map is no longer available.
This video features Erik and his friend Paul shooting down the trails of Delaveaga on a pleasant November morning.