55th parallel north
The 55th parallel north is a circle of latitude that is 55 degrees north of the Earth's equatorial plane. It crosses Europe, Asia, the Pacific Ocean, North America, and the Atlantic Ocean.
At this latitude the sun is visible for 17 hours, 22 minutes during the summer solstice and 7 hours, 10 minutes during the winter solstice.[1]
This latitude also roughly corresponds to the minimum latitude in which nautical twilight can last all night near the summer solstice.