Travellers camped in Lovemead Car Park in Duke Street, Trowbridge, on Wednesday were moved on by Wiltshire Police after they were served with a Section 61 notice.
The travellers arrived in the car park early on Wednesday in several large caravans, taking up almost half of the car park.
Officers from Wiltshire Council visited the car park and carried out a welfare assessment, before informing the travellers that they needed to leave by 6pm or they would be served with a section 61 notice by Wiltshire Police.
The notice, which gives police the power to seize and remove the vehicles, meant the travellers had until 8am on Thursday to leave the site, which they did.
Inspector Chris Chammings said: “We worked closely with Wiltshire Council, who own the land, to ensure that they were moved on safely and promptly.”
The section 61 notice also means that police can seize and remove the vehicles if the travellers return to the site within three months.
A spokesman at Wiltshire Council said: “We are pleased that we were able to work with the police to move them on quickly. We will be clearing up any rubbish they have left behind.”