Grid north is marked by the blue lines on a flat Ordnance Survey map and they do not take account the Earth being round. Magnetic north is the direction a compass points.

The map reading skills covered by presenter Joe Crowley include: contour lines, co-ordinates, eastings and northings, grid references and navigation using a compass.

How Get Rid of the Grid on Google Earth. Google displays a series of translucent white latitudinal and longitudinal grid lines over its 3-D maps in some versions of Google Earth.

Grid north is the blue line on an OS map that points to the North Pole. True north is the direction of lines of longitude that also converge at the North Pole, but this varies from grid north as ...