Appleby Horse Fair violence warning
Police have said they will not tolerate street fighting and violence of any form at this year's Appleby Horse Fair.
Police have also reminded people not to bring weapons into the county.
Thousands of people attend the annual event, which is billed as one of Europe's largest gatherings of Gypsies and travellers.
Last year arrests were down 50% on the previous, but some travellers complained of heavy-handed tactics by the police.
A report into the 2010 event in June concluded that organisers and police failed to balance the needs of the different communities involved.
Police said they expected 50,000 people at this year's event.
They warned the trading of BB guns was prohibited at the fair and stall holders found selling them would be ejected from the event and banned from future events.
They also warned other items that could be seen as weapons - such as baseball bats or whips - that are carried around in a public place without a valid "purpose" would be confiscated.
Assistant Chief Constable Jerry Graham, who is in charge of the Appleby Fair policing operation, said: "Planning for this year's event is well under way and before visitors begin their journey to Cumbria, we want to remind troublemakers to stay away.
"As part of the multi-agency approach to the fair, we aim to help facilitate a safe environment for visitors and local people to enjoy and, my message to the minority who may be intent on causing violence is that you are simply not welcome.
"Officers in high visibility uniform will be on hand throughout the event to provide a proportionate policing response to any issues that may arise."