Irvine Open Space is generally closed. On Open Access Days (the 2nd or 3rd Saturdays of the month) one can access this great bowl of trails. We did 3/4 of the trails into the Shady Canyon - the 4th being closed due to damage. A great area to train with moderate elevation gain. To add a bit more mileage, we walked under Hwy 133 to Barbara's Lake and Dilly Nature Preserve. Great location for Spring, winter hikes.