What must hydrographic charts for navigation include regarding landmarks?

Hydrographic charts for navigation are essential tools that provide detailed information about bodies of water and surrounding areas. The inclusion of sufficient topography to show landmarks useful for navigation is critical for safe and effective maritime travel.

This information allows mariners to identify their position, navigate effectively, and avoid obstacles that might not be immediately visible from the water. Landmarks serve as vital reference points, helping navigators confirm their location and course. Properly represented topographic features, such as coastlines, river entrances, and prominent geographic formations, assist in situational awareness and making informed decisions while at sea.

The other options do not encompass the comprehensive needs of navigation. Relying solely on known hazardous landmarks would not provide the necessary breadth of information for safe passage. Focusing exclusively on underwater features neglects the importance of surface navigation, which is equally vital. Lastly, aerial views do not serve the purpose of hydrographic charts, as these charts are specifically designed to offer underwater and surface navigation information rather than visual representations from an aerial perspective.