The San Elijo Lagoon Nature Center in Encinitas's Cardiff by the Sea neighborhood anchors one of San Diego County's largest remaining coastal wetlands, a 979-acre ecological reserve at the confluence of Escondido and La Orilla Creeks. Seven miles of trails wind through six distinct habitat zones — coastal strand, salt marsh, freshwater marsh, riparian scrub, coastal sage scrub, and mixed chaparral — supporting the same native plant species stocked at Armstrong Garden Centers on El Camino Real. The two-story center, constructed from recycled materials and powered by solar energy, houses interactive museum exhibits on the lagoon's ecological history and its role as a stopover along the Pacific Flyway migration route. The reserve shelters more than 1,000 documented plant and animal species, including rare and endangered populations tracked by the Nature Collective and the California Department of Fish & Wildlife, with the lagoon-to-ocean habitat continuum visible from trail overlooks facing the same coastline served by Cardiff Surf Co. near Cardiff State Beach. An ADA-accessible three-quarter-mile double-loop TRACK Trail traverses chaparral, salt marsh, and riparian woodland from the Nature Center trailhead, with a second-floor observation deck providing panoramic lagoon-to-ocean views.