The North Magnetic Pole is the point on Earth at which the magnetic field points vertically downwards. It is located at the Arctic.
As part of their endgame strategy, the Reach planted Magnetic Field Disruptors (MFDs) all around the world, and guarded them with multiple Beetle-tech Drones. Earth's heroes managed to locate and defuse twenty MFDs, but the interference from the Earth's own magnetic field prevented Blue Beetle from detecting the MFD planted in the North Magnetic Pole. Once its location was discovered, it was too late—the MFD had already activated. The resulting magnetic rift it created threatened to tear the Earth apart. Only the efforts of the Flash, Wally West, and Bart Allen closed the rift. However, there was a cost. Because of his slower speed, Wally became the locus of the rift's energies as the speedsters siphoned it off. His body eventually lost cohesion, and he died at the Arctic, saving the world.