What does a safe altitude indicate in terms of navigation?

A safe altitude is defined as the height at which an aircraft can fly without the risk of colliding with obstacles. In navigation, this generally means maintaining an altitude that is free from obstacles within a specific radius, often cited as within 100 nautical miles. This ensures not only the aircraft's safety but also contributes to a level of situational awareness and navigation confidence.

To clarify the context of the other options: the altitude for landing pertains to the specific approach and landing phases and does not encompass obstacle clearance. The normal flying altitude refers to levels typically used during cruise flight, which may not guarantee obstacle clearance. The highest point on a specific route does not account for potential obstacles that could be below that point. Hence, the focus on a safe altitude as an indication of being free from obstacles within a notable distance is vital for flight safety and navigation.