People in Peterborough are being urged to help clamp down on drink and drug driving.
Throughout June and July police will carry out roadside spot checks.
Cambridgeshire Police say they often pull over drivers who believe they are okay to drive but are, in fact, well over the limit.
Last year 860 people were arrested in Cambridgeshire on suspicion of driving under the influence of drink and drugs.
For more information on drink and drug driving visit the force s road safety pages.