What is a benchmark in navigation?

A benchmark in navigation is defined as a man-made marker that indicates a specific point of elevation above sea level. These benchmarks are commonly used by surveyors, engineers, and navigators to establish elevation data accurately. They are typically made of durable materials such as metal or concrete and feature a marked point or plate that displays the elevation information.

This elevation data is crucial for various activities, such as topographical mapping, construction projects, and military operations that require precise elevation readings for planning and executing maneuvers. Understanding the location and significance of benchmarks enhances a navigator's ability to interpret maps accurately and relate their position to the terrain.