London, June 20 (Reuters): Over 20,000 druids, spiritualists and revellers are expected to descend on Stonehenge early tomorrow to celebrate the annual summer solstice at the ancient stone circle.

A spokesman for the Druid network said they expected a strong turnout on the longest day of the year in the northern hemisphere due to the good weather.

The prehistoric stone monument is open to the public throughout the year, but the solstice allows revellers a rare opportunity to walk among the 20-tonne stones. Druids are drawn to Stonehenge because they believe it was a centre of spiritualism more than 2,000 years ago.