Police are facing abuse from a handful of solstice revellers near Avebury.
More than 300 vehicles have parked up along the Ridgeway as access for a mile around the ancient site is cordoned off.
Hundreds of people arrived over the last couple of days, with more turning up this afternoon.
Tempers are getting frayed, with some of those at the site arguing with police at the entrance to the Ridgeway.
Wiltshire Police closed part of the byway to protect farmland and maintain public safety.
They said: "We have taken the difficult decision to prevent further access to part of the Ridgeway, near Avebury, to maintain public safety and prevent potential damage to nearby farmland.
"This is in response to large numbers of people and vehicles in the area."
Cars and vans are parked along the side of the road, and police are trying to move people on.
Vehicles can be seen up on verges and in farm gates in nearby villages.
A police spokesperson urged anyone wanting to celebrate solstice to "do so safely and where possible from home".
READ MORE: drumming heard from miles around
Official access to Stonehenge which is about 24 miles (38km) away, has been stopped due to Covid.
Solstice is marked at sunrise on June 21 - tomorrow morning at around 5am.
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