Countries and regions across the Northern Hemisphere will witness the summer solstice on Sunday, marking the astronomical beginning of summer.

The summer solstice is Sunday, marking the longest day of the year in the Northern Hemisphere and the start of astronomical summer

The summer solstice is Sunday, marking the longest day of the year in the Northern Hemisphere and the start of astronomical summer

Countries and regions across the Northern Hemisphere will witness the summer solstice on Sunday, marking the astronomical beginning of summer.

The summer solstice on June 21 marks the longest day of the year in the Northern Hemisphere and the official start of astronomical summer

The summer solstice marks the longest day and the start of astronomical summer.