Boulders and mounds of earth have been formed into a ring of defences around an Oxford estate to prevent it being invaded by trespassing travellers.

The artificial barriers have been built on grass verges along Grenoble Road and Watlington Road that form a boundary around Blackbird Leys and Greater Leys.

Oxford City Council and Oxfordshire County Council installed the rocks, boulders and earth on verges most popular for illegal campsites and caravans.

The move comes after it was revealed a traveller family has been evicted from camps in Grenoble Road and Watlington Road 14 times in the past two years.

Mark Gold, of Oxfordshire County Council's gypsy liaison services, said: "The boulders have been put down to prevent travellers parking on the grass verge following complaints by local residents about noise and waste left behind.

"We believe they will help prevent travellers setting up camp there in future."

The first mounds of earth were initially placed on verges at Watlington Road by council workers before Christmas and, despite being branded ugly, will be seeded later in the year.

Last week, large boulders were placed along Grenoble Road and outside the Kassam Stadium to complete the defence project.

Val Smith, Leys county councillor, said; "It's unfortunate because we would love not to have the boulders and earth left there.

"They're not exactly great works of art.

"But we must have them because it costs both councils so much more to take the travellers to court or pay for the land to be cleaned up."

In the past four years, a family known locally as the Loveridges has been kicked off private land 32 times in Blackbird Leys, Littlemore and Cowley.

This included 14 occasions of illegally setting up camp in Watlington Road and Grenoble Road.

In total, they have been moved off county council land at least 13 times, city council land seven times, South Oxfordshire District Council land twice and private land three times.

In March, police warned travellers they would crack down on any family ignoring eviction orders after a landmark court case.

A conviction was secured against four travellers who illegally returned to a temporary campsite in Kennington, despite being subject to an eviction order.

It was the first conviction of its kind in the country and was hailed by police.

They said it had clarified the law, allowing them to deal with travellers more effectively.