The 61st parallel north is a circle of latitude that is 61 degrees north of the Earth's equatorial plane. It crosses the Atlantic Ocean, Europe, Asia and North America.
At this latitude the sun is visible for 19 hours, 16 minutes during the summer solstice and 5 hours, 32 minutes during the winter solstice.[1]
This latitude also roughly corresponds to the minimum latitude in which civil twilight can last all night near the summer solstice.