Hike through one of Southern California's first greenbelt parks -- the James Dilley Preserve near Irvine.

The James Dilley Greenbelt Preserve, a unit within Orange County's Laguna Coast Wilderness Park, dates back to a landmark purchase by the city of Laguna Beach in 1978. Environmentalist James Dilley helped champion the concept of "greenbelts," or parcels of open space between cityscapes, back in that era.

The trail system in the preserve is pieced together out of former bulldozed roads and current utility roads. The three-mile loop described here covers the best trails and touches upon the best sights the preserve has to offer. The first stretch (Canyon Trail) doubles as a portion of the 1.8-mile long Bea Whittlesly Loop self-guiding nature trail, which features posts keyed to a brochure available at the trailhead.

Park at the Dilley staging area on the east side of Laguna Canyon Road (Highway 133), 0.2 mile north of the Highway 73 toll road overcrossing. Head east across a field of sage and buckwheat on the Canyon Trail, which at first gains elevation gradually and stays near the bottom of a small canyon dotted with gorgeous specimens of coast live oak and California sycamore. At about 0.7 mile the trail begins a steeper ascent, curling upward through a patch of prickly-pear cactus (look or listen for cactus wrens). At 1.0 mile, you arrive on top of a buried water reservoir on a 624-foot knoll. Take a look around. The Leisure World development lies to the east, the open spaces of the Laguna Coast Wilderness Park sprawl to the south and west, and if it's clear enough you can spot the 10,000-foot-high summit of Mount San Antonio floating above the hazy urban landscape in the north.

Next, slip down the slope east of the reservoir to reach a maintained fire road following the ridge top. You'll want to head north -- not on the gravel road that descends smoothly to the north and east, but rather on the somewhat rougher "Edison" road on the right that stays more or less underneath the high-voltage power lines. That route takes you down to and then right along the shoreline of beautiful Barbara's Lake, the larger of two small lakes that constitute Orange County's only naturally formed inland bodies of water. The lakes are geologically described as small sag ponds, located where the ground has subsided due to movements along a fault. Since Barbara's Lake is shallow and its drainage area is small, it is believed that artesian springs on the lake bottom help keep it full no matter what the season.

At Barbara's Lake and elsewhere in the Laguna Coast Wilderness Park, you will find large plaques with original plein air paintings by local artists. Ultraviolet-resistant coatings on the paintings have kept them from fading much over a number of years.

From the gravel road at the south end of Barbara's Lake, you can make a side trip under Laguna Canyon Road's arched overpasses to reach the brand-new James and Rosemary Nix Nature Center on the far side (open 9 a.m. to 4 p.m. daily; free admission). What are the strange cavities on the undersides of those overpasses? They are entrances into the hollow interiors of the concrete structures for use by bats and swallows.

Exclusive of the side trip under the overpasses, the remainder of our designated three-mile route goes south from the gravel road on nearly a bee-line course back to the Dilley staging area.