The parallel of latitude that is approximately 66.5 degrees north of the equator and that circumscribes the northern frigid zone.
a line of latitude south of the north pole
a line of latitude near but south of the north pole; it marks the northernmost point at which the sun is visible on the northern winter solstice and the southernmost point at which the midnight sun can be seen on the northern summer solstice
a line of latitude near but to the south of the north pole; it marks the northernmost point at which the sun is visible on the northern winter solstice and the southernmost point at which the midnight sun can be seen on the northern summer solstice
