How long are days and nights in Hammerfest Norway?

Hammerfest is above the Arctic Circle, so near the summer solstice (around June 21st), there will be 24 hours of daylight and near the winter solstice (about December 21st), there will be 24 hours of darkness. Near both equinoxes, like the rest of the world, there will be 12 hours of light and 12 hours of darkness.