Abstract
Nautical charts are important document for safety navigation. There are many map projections used to build charts with different applications in navigation. It is common knowledge that only the Mercator projection satisfies the basic requirements of the nautical chart. Therefore, today, most of the sea charts being used on ships are Mercator charts. However, the increasing distortion to the poles of the earth is the weak point of Mercator charts. Thus, it is necessary to find out the other projections instead of Mercator charts in the areas with large distortion. The aim of this research is to focus on the distortion of Mercator projection and its effect on safe navigation.