The scale shows how much bigger the real world ... heights by a black dot with a number next to it. The number is the height above sea level in metres. The blue triangle represents a triangulation ...
so anything outside the range of 15 to 20 inches could throw off the scale of a space and look like a visual oops. Adjust ...
The number is the height above sea level in metres ... Contour lines are usually drawn at 10 metre intervals on a 1:50,000 scale map and at 5 metre intervals on a 1:25,000 scale map.