Anger at travellers' camp
A dozen families arrived at the field on Friday and worked around the clock to make the site their home.
They laid a hard surface, put up portable toilets, dug a cesspit and 12 separate plots were fenced off.
It is understood the site is privately owned by one or more of the travelling community but no planning permission for residential use has been made.
The travellers insist they are using the land at Southend Lane after failing to find an adequate home elsewhere in the county.
A spokesman for the group, called Sam, said they wanted to be good neighbours.
"We are honest, law abiding citizens who just want a place to live," he said.
"We have applied to the council to give us a home on a number of occasions, but with no joy.
"We don't want to cause our new neighbours any harm and want to get on with them as anyone else would."
The arrival of the travellers confirmed the worst fears of residents who said they had warned Forest of Dean District Council this could happen more than two months ago.
They said men had been seen looking around the site, checking the local sewerage system and even made contact with their soon-to-be neighbours.
One resident, who didn't want to be named, said: "We warned the council that this would happen"
"The guys who were looking around said that they were planning to put horses on the site, but horses don't need electricity and a cesspit."
"They arrived at 5pm on Friday, worked through until about 10pm and then started at 6am on Saturday."
"There must have been at least 70 deliveries of stone to the site during the day on Saturday."
It is understood Forest of Dean District Council attempted to get a court injunction to stop the work, but it was turned down.
Forest of Dean MP Mark Harper said as no planning permission had been granted an enforcement notice would have to be issued.
Meanwhile, the Conservative MP has called for urgent reform into the way the travelling community find land to settle on.
"The current situation is deeply unsatisfactory," he said.
"The travellers feel that the local authority have not made enough local provision so they can therefore get away with this.
"They've not done what anyone else would do and go through the correct channels.
"In this instance the local authority did everything they could to prevent this from happening."
Forest of Dean District councillor Jayne Horne, whose Tibberton ward neighbours Southend Lane, echoed those views.
"Unfortunately the council's hands are tied on this issue and the powers that be are very sympathetic to travelling communities." she said.
"As they own the land it becomes a planning issue and the wheels move and grind so slowly."
Coun Horne said along with fellow councillor Len Lawton whose Newent Central ward covers Southend Lane, she would do all she could for residents.
"We will do all we can to help them, the law as it stands is wrong," she said.
The latest Government figures for January show there are 2,539 gypsy and traveller caravans in the south west – the highest ever and 893 of these were on sites without planning permission and only 317 were facing legal action as result.
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