Nautical hazards are a common concern for sailors, as they can cause serious damage to ships and put lives at risk. The term 'nautical hazard' encompasses a variety of potential dangers, including icebergs (BERG), shallow areas with submerged rocks (REEF), shallow areas with sandbanks (SHOAL), thick FOG (FOG), and frozen sea water (SEAICE). All of these hazards can be difficult to navigate around, and can lead to serious consequences if not taken into account.