The Batiquitos lagoon consists of 610 acres, both great for hiking and dog-friendly, along with 55,000 acres of basin.  The watershed basin covers grounds in the cities of Carlsbad, San Marcos and Encinitas, with its primary freshwater tributaries being from the San Marcos Creek.

Personal Experience: This is a great place for a leisure walk.  It is incredibly dog and kid-friendly.  The nature center offers an educational insight into the lagoon with plant and animal information.  Make sure to pick up a pamphlet at the center to help you identify different plants on your walk!  We found a tunnel for those of you into that thing.  It seems to go pretty far.  Please comment if you know where it ends up!

There's a cool storm drain out here.  Another day, another adventure!