Summer solstice is the longest day of the year in the northern hemisphere.
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Visitors lean on the stones at Stonehenge, which was built in three phases between 3,000 B.C. and 1,600 B.C.
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Thousands of revelers visit the ancient stone circle at Stonehenge in Salisbury, England, to glimpse the sun on the summer solstice.
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About 23,000 sun watchers gather on the Salisbury Plain about 80 miles southwest of London for summer solstice.
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