Where and when is the Sun at its zenith in different seasons of the year?

At all points beyond the Arctic Circle, at least once a year, in the interval between the days of the spring and autumn equinox, it can last 24 hours. At points located exactly on the polar circle, this occurs on the summer solstice (June 20-21) at all points between the northern tropic and the equator, at least twice a year, the sun is at its zenith. Precisely in the tropics, this occurs on the days of the spring (March 20-21) and autumn (September 22-23) equinox.