Map guides
Practical methods for measuring maps, checking coordinates and understanding uncertainty.
Measure land area in square metres and hectares
Draw a useful boundary and distinguish a map estimate from an official area.
Measure a map distance without cutting corners
Follow bends and separate straight-line distance from an actual route.
Understand uncertainty in map measurements
Find the main source of error before adding decimal places.
Choose the right coordinate system in Sweden
WGS84, SWEREF 99 and RT90 are not interchangeable labels.
Check a converted coordinate step by step
Verify the location, axes and projection before trusting a converted number.
Plan a drawn sea route in nautical miles
Estimate distance and time while keeping navigation decisions separate.