A record crowd of about 36,500 revellers has welcomed the dawn of the Summer Solstice at Stonehenge.
The number of people attending the event caused roads in the area to become gridlocked in the hours leading up to sunrise at 0458 BST.
Druid ceremonies took place alongside music and Morris dancing, however overcast skies obscured the sun.
Police praised the crowd and said there had been only 37 arrests, for minor disorder and drugs offences.
Supt Nick Ashley said: "The celebration has been peaceful and enjoyable for the majority who were present to celebrate in a safe manner.
"It is disappointing that a small number of people chose to ignore the conditions of entry and brought with them illegal drugs but this was dealt with effectively."
The event to mark the dawn of the longest day in the Northern Hemisphere has grown in popularity since a four-mile exclusion zone around the site was lifted nine years ago.
English Heritage, which manages the ancient monument, said the car park was full with 6,500 cars two hours before sunrise.
Meanwhile the main route into Stonehenge, the A303, was closed due to volumes of traffic.
Peter Carson, head of Stonehenge, said: "We were expecting it to be busy this year, but we had ensured that it has been a peaceful and enjoyable solstice.
"There has been a great atmosphere and where else would you want to be on midsummer's day?"
Police drafted in extra officers and said there would be a zero-tolerance approach to drugs and drunkenness, with an alcohol limit of four cans of beer or a bottle of wine per person imposed by English Heritage.
Druid King Arthur Pendragon told the BBC shortly before sunrise: "It's a very nice atmosphere and everything's fine at the moment.
"There have been more police present this year, more security, but everything's passed off very jovially and everyone's in a good mood.
"And the police for the most part are wishing people a happy solstice and so are the security guards."
English Heritage had issued an advisory note to visitors which warned: "Summer Solstice is not a good time to experiment with drugs - the crowd, the noise and the sheer size of the place are likely to make any bad reaction much, much worse."
Meanwhile, a limit of 200 tents was set at a field near the Avebury Ring after residents complained about the number of visitors to that site in 2008.