Get intimate with bat rays and pickleweed at the Chula Vista Nature Center.

Spy on the secret, subterranean life of a worm; ogle a heron or an egret; pet a bay ray or a leopard shark; get personal with pickleweed and cordgrass; sniff the sage-tinged salt breeze as you stroll an upland pathway along San Diego Bay. Enjoy this and more at the Chula Vista Nature Center, now in its 14th year of serving the public.

Dedicated in 1987, the nature center's 11,000-square-foot interpretive building overlooks the Sweetwater Marsh National Wildlife Refuge, which is the largest remaining parcel of saltwater marsh rimming San Diego Bay. This biologically superproductive swatch of land is emerging from a dingy past dominated by such abuses as chemical manufacturing, illegal dumping, and highway construction.

Step inside the center and get acquainted with the lives of dozens of interesting creatures from air, sea, marsh, and upland domains. Interpretive panels, hands-on exhibits, aquaria, and terraria educate as well as entertain you. Just outside there's a 4500-gallon petting pool stocked with leopard sharks, sting rays, and bat rays. A new, expanded shark and ray pool will soon be under construction.

A bit farther afield you'll find a recently enlarged raptor enclosure, a new shorebird exhibit, and a clapper-rail exhibit, where a captive-breeding effort is now in progress to aid the survival of this endangered species of bird.

You can also stroll a mile or more on gravel-surfaced interpretive trails, spotting birds (220+ species recorded so far) and learning about the site's role in processing kelp for use in manufacturing gunpowder during World War I. You'll see the result of years of volunteer effort spent in the restoration of salt-marsh and upland habitats to conditions approximating those of prehistoric times. On clear days, the trailside view includes downtown San Diego's high-rises, the Coronado bridge, the Coronado Islands off Baja's coast, and the rumpled skyline of hills and mountains to the east. You'll maximize your learning on foot by taking advantage of docent-guided walks offered Wednesdays, Saturdays, and Sundays at 2 p.m.

Getting to the Chula Vista Nature Center is easy. Exit Interstate 5 at E Street, turn west, park, and board a free shuttle bus that runs at approximately 20-minute intervals from 10 a.m. to 4 p.m., Tuesday through Sunday. (The nature center is closed on Mondays.) The San Diego Trolley's Chula Vista Bayfront Station is close to the shuttle pickup point as well. For more information, phone the center at 619-409-5900.