TOMORROW is the longest day of the year, marked by the Summer Solstice at Stonehenge, and this is everything you need to know if you're going.

The festival attracts thousands, from pagans and druids to families and tourists, as it's one of the only times of the year to get up close to the stones.

This year's solstice celebrations run from 7pm on Tuesday, June 20, until 8am on Wednesday, June 21.

It is free to attend and no tickets are needed, but English Heritage has outlined a number of conditions that all attendees must abide by.

The following are not permitted at the Stonehenge Summer Solstice:

  • Alcohol and illegal drugs
  • Camping equipment, fires or BBQs
  • Drones
  • Sharp objects, including any glass
  • Amplified music
  • Duvets or sleeping bags

Climbing or standing on the stones is prohibited and people are not allowed to sleep on the ground.

A spokesperson for English Heritage said: "Stonehenge is a World Heritage Site, a Scheduled Ancient Monument and is seen by many as a sacred place.

"We ask that all those attending respect it and those celebrating around it."

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The sun is predicted to rise behind the Heel Stone, shining a ray into the heart of Stonehenge, at 4.49am.

Limited parking, which costs £15 per car, is available from 7pm on Tuesday and last admissions are at 6am or when the car park is full.

The monument field will shut at 8am and the car park will be cleared by noon.

Alternatively, Salisbury Reds will run a bus service up to Stonehenge Visitor Centre from 6.30pm on Tuesday until 1am on Wednesday every 15 minutes.

The '333' service leaves from New Canal and calls in at Salisbury Rail Station and Amesbury Town Centre.

A service taking people back to Salisbury will start again at 4am and run frequently until 10am.

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There is a 30-minute walk from the drop-off point to Stonehenge and visitors are advised to bring sensible footwear and a torch.

Bicycles can be safely locked up in designated areas of the Solstice car park and it is possible to make the two-and-a-half mile journey from Amesbury on foot.

For those who would prefer to watch the Solstice from home, they can do so by watching the live stream on the English Heritage YouTube channel here.

Stonehenge is closed on Wednesday for normal admissions and will re-open again at 9am on Thursday, June 22.