Avon and Somerset police have served eviction notices to owners of 15 mobile homes who moved onto the Blaise Castle estate.
The travellers have until 5pm to leave the site, according to Avon and Somerset Police.
Travellers on the site, from Dublin, told our sister newspaper Bristol Post yesterday they had parked there on Friday as they had no where else to go.
A police spokesperson today said they had ordered the travellers to leave under a Section 61 notice.
They said the Section 61 had been used as there had been offences including dogs running free, litter, ponies in makeshift paddocks and damage to grass.