What does a nautical chart scale indicate?

• A. The depth contour accuracy
• B. The ratio of map distance to real-world distance
• C. The chart’s color scheme
• D. The orientation of north

Answer: (B)

A nautical chart scale shows the ratio between distances on the chart and real-world distances. This tells you exactly how far apart two points on the map are in the real world. For example, a scale of 1:50,000 means that 1 unit on the chart corresponds to 50,000 of the same units in reality, so 1 centimeter on the chart would equal about 0.5 kilometers on the water. This is what lets you translate measurements you take on the map into actual travel distances and plan routes, time, and resource needs. The other aspects—depth contour accuracy, chart colors, or which way north points—do not define distance on the map in the same way.