Thousands of people from across the world are expected to gather at Stonehenge in southern England to mark the summer solstice. The ancient monument is a focal point for spiritual rituals on the longest day of the year and the first day of astronomical summer. (AP Video by Mustakim Hasnath)

How the sun aligns on the summer solstice, the longest day of the year

Thousands of people from across the world are expected to gather at Stonehenge in southern England to mark the summer solstice. The ancient monument is a focal point for spiritual rituals on the longest day of the year and the first day of astronomical summer. (AP Video by Mustakim Hasnath)