Spanish Waters looks like an inland lake, but it's actually connected to the ocean by a navigable channel that doesn't show in this picture. Spanish Waters provides anchoring room for hundreds (thousands) of boats, and adequate bus service to and from Willemstad.
The large body of water inland of Willemstad is also accessible by a large channel that doesn't show here, but all of the oil refineries are back there, and they have to swing the floating bridge out of the way to let boats through, so we didn't take Ocelot there.