In summer it usually takes place between the 20 and 22 June, although the next 22 June solstice will not take place until 2203.

UNESCO: UK National Commission for UNESCO - Longest crowds for the longest day, as Stonehenge solstice visitors reach 23,000

Held on June 20, the summer solstice, the event called on people to participate in a sunrise-to-sunset endurance relay, with donors pledging various amounts per hour of participation.

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Summer solstice starts at 05.04am on June 21 if you have yet to enter in your diary the UK government's self-imposed deadline.

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