Jim Jim Falls is Kakadu's most dramatic waterfall, a high drop into a deep gorge in the southern part of the park. Reaching it by road is a dry-season, 4WD-dependent undertaking, and even then access can close with conditions.
Check current park reports before setting out, carry plenty of water, and leave more time than the map suggests. If the road is closed in the wet season, scenic flights may be the only realistic way to appreciate the falls in full flow.