Mound Key is located in Estero Bay, and is only accessible by boat. There are no facilities on the island. Interpretive displays can be found along the one main trail that spans the width of the island. There are many mounds along the trail, and the largest rising to a height of more that 30 feet above sea level. If you can brave the mosquitoes the view from the top of the tallest mound provides a wonderful vista of the bay.