People living on a housing estate on a former RAF base in North Somerset have set up a round-the-clock checkpoint to stop travellers moving onto the site.
Last weekend a number of caravans moved onto the Locking Parklands estate near Weston-super-Mare.
The landowners went to court and obtained an eviction notice ordering the group to move on.
Residents' spokesman Elliot Steed said they are prepared to stay "as long as it takes" to protect their community.
"They have been here before and left the place in a bit of a mess," he said.
"Because of their reputation a lot of people are a bit nervous of them.
"It's very important the community stands up to them," Mr Steed added.
North Somerset Council does not run a transit site for travellers because it says it cannot justify the cost.
Councillor Elfan Ap Rees said: "They cost literally millions a year to run. We cannot justify that and our priority has to be local people.
"There are transit sites available at Westonzoyland and Avonmouth but we cannot force the travellers to use them."