EDITION 13 FOR 2017 - 2018 PUB.200 SAILING DIRECTIONS ANTARCTICA Sailing Directions are published by the U.S. National Geospatial- Intelligence Agency (NGA). Sailing Directions, covering the harbors, coasts, and waters of the world, provide information that cannot be shown graphically on nautical charts and is not readily available elsewhere. Sailing Directions are intended to assist mariners in planning ocean passages. Sailing Directions include detailed coastal and port approach information which supplements the largest scale chart.