Buttermilk Sound R208 There is a distinct shoal building into the ICW. It is located about 400 feet SE of R208. At 31 8.744 N and 081 20.984W. It shows clearly on the Navionics Sonar Charts. If you are using NOAA charts or other cartography, you might just put a warning waypoint on your charts. Being that it is on the red side of the channel this is more of a concern headed south when you naturally stay closer to the red side of the ICW.