There are miles of walking/hiking trails on the north side of the BATIQUITOS LAGOON (one of 3 lagoons in Carlsbad), some of which border the Park Hyatt Aviara Resort Golf Course, with great vistas of the hills, wooded areas, and the lagoon. The area is a wildlife preserve and great for bird watching. Markers will help you keep track of distance and occasional signs will help you identify wildlife you see.
No swimming, fishing, or boating is allowed. One day a year they allow kayaks on the lagoon for the annual clean-up.
There are several places to park along Batiquitos Drive (which can be access at the east end from Aviara Parkway, and from the west end off Poinsettia). Dogs are welcome – on leashes.