Nearly 40,000 people gather at Britain's Stonehenge to hail summer solstice

Revellers dressed in Aztec costume celebrate the summer solstice on Salisbury Plain in southern England on June 21, 2014. -- PHOTO: REUTERS
Revellers dressed in Aztec costume celebrate the summer solstice on Salisbury Plain in southern England on June 21, 2014. -- PHOTO: REUTERS
The sun rises over the standing stones at the prehistoric monument Stonehenge, near Amesbury in Southern England, on June 21, 2014, as revelers gather to celebrate the 2014 summer solstice, marking the longest day of the year. -- PHOTO: AFP
The sun rises over the standing stones at the prehistoric monument Stonehenge, near Amesbury in Southern England, on June 21, 2014, as revelers gather to celebrate the 2014 summer solstice, marking the longest day of the year. -- PHOTO: AFP
A modern druid named Merlin stands as the sun rises at the prehistoric monument Stonehenge, near Amesbury in Southern England, on June 21, 2014 as revelers gether to mark the summer solstice, the longest day of the year. -- PHOTO: AFP
A modern druid named Merlin stands as the sun rises at the prehistoric monument Stonehenge, near Amesbury in Southern England, on June 21, 2014 as revelers gether to mark the summer solstice, the longest day of the year. -- PHOTO: AFP
A reveler called Mad Alan (real name) celebrates with his grandson Tobias (up) as the sun rises at the prehistoric monument Stonehenge, near Amesbury in Southern England, on June 21, 2014 marking the summer solstice, the longest day of the year. -- P
A reveler called Mad Alan (real name) celebrates with his grandson Tobias (up) as the sun rises at the prehistoric monument Stonehenge, near Amesbury in Southern England, on June 21, 2014 marking the summer solstice, the longest day of the year. -- PHOTO: AFP
Revelers gather as the sun rises at the prehistoric monument Stonehenge, near Amesbury in Southern England, on June 21, 2014 to mark the summer solstice, the longest day of the year. -- PHOTO: AFP
Revelers gather as the sun rises at the prehistoric monument Stonehenge, near Amesbury in Southern England, on June 21, 2014 to mark the summer solstice, the longest day of the year. -- PHOTO: AFP
Revelers watch and take photos as the sun rises over the standing stones at the prehistoric monument Stonehenge, near Amesbury in Southern England, on June 21, 2014, as revelers gather to celebrate the 2014 summer solstice, marking the longest day of
Revelers watch and take photos as the sun rises over the standing stones at the prehistoric monument Stonehenge, near Amesbury in Southern England, on June 21, 2014, as revelers gather to celebrate the 2014 summer solstice, marking the longest day of the year. -- PHOTO: AFP

LONDON (AFP) - Druids and pagans were among the nearly 40,000 people who gathered at Britain's ancient Stonehenge monument to hail the summer solstice at dawn on Saturday.

The police said they arrested 25 people, mostly for drug offences, during the all-night celebration to mark the longest day of the year.

"We are pleased that the solstice celebrations have been enjoyable events for the majority of people attending," said a police spokesman.

The 5,000-year-old stones stand between 3m and 6m high and are arranged in concentric circles.

Historians estimate they were erected sometime between 3000 BC and 1600 BC.

The monument became a World Heritage Site in 1986 and despite years of research and study, the reason behind its construction remains a mystery.