Example image of eyePlorer eyePlorer map for 'Magnetic declination': Compass True north Contour line United States Iron Magnetite Ore Secular phenomena Metes and bounds North Pole Aeronautical chart Nautical chart Empirical modelling National Geophysical Data Center National Oceanic and Atmospheric Administration Magnetic deviation Bearing (navigation) Air navigation Global Positioning System VHF omnidirectional range Voyages of Christopher Columbus Absolute bearing Breton plotter Grid north Toronto Magnetic and Meteorological Observatory Henry Gellibrand Isoclinic line Robert Hues Devil's Sea Winnetka, Illinois Runway Admiralty chart Paleomagnetism Shen Kuo Thomas Hutchins (naturalist) Cape Agulhas Francesco Denza Johan Maurits Mohr Martín Cortés de Albacar Korean Air Lines Flight 902 Mecca Time Symmes Purchase Technology of the Song Dynasty Canadian airspace Edward Wright (mathematician) Gaudineer Scenic Area Long Valley Caldera Meridian (geography) North Notam Check