We were intrigued when we read that this is the only trail at this national seashore that allows you to walk from the Atlantic Ocean to the Mosquito Lagoon, crossing the entire barrier island.
Park across the road from the trailhead and visit the Atlantic ocean before crossing onto the Castle Windy Trail. The trail is shaded and a breeze is ever-present. There is a bench halfway down the trail that leads to Mosquito Bay and a picnic area.
We saw so many islands in the lagoon that we'll be back to kayak and explore them and may grab a permit to camp on them. One could spend hours on the beach looking at shells and watching the birds.