The Arctic (sometimes called the Polar) Circle is a theoretical line encircling the globe. It is the most northerly of five major circles of latitude shown on maps of the Earth, marking the northernmost point at which the noon sun is visible above the horizon during the December solstice, and the southernmost point at which the midnight sun is visible at the June solstice. Along the coast of Norway, a monument has been placed on a rocky islet located on the approximate latitude of the Arctic Circle. The actual latitude varies based on the axial tilt of the earth and other factors such as tidal attraction, but in rough terms it is about 66 degrees, 33 minutes north of the Equator.