Aiken canyon is open for hiking only on weekends and Mondays. It is on highway 115 directly across from Turkey Creek Ranch. There are 5-6-ish miles of trails here including an option to go up a hill for views or a long jog up to some cabin ruins and old spring. The spring trail gets more secluded quickly and continues on beyond the park boundaries if you do a bit of climbing. Both are worth seeing. Ecology is more southwestern than trails just a few miles further north. Lots of scrub oak, good views down to the Spanish Peaks.