Highways England has warned drivers in Cambridgeshire that roads “may be busier than usual” this weekend because of the Duxford Air Festival.
The giant show at the Imperial War Museum takes place on Saturday and Sunday (May 27 and 28).
The roads agency said in a statement: “Highways England is working in partnership with IWM Duxford and local authorities to help get traffic to and from the event efficiently and safely and to keep traffic flowing.
“Drivers should check conditions before setting off and not travel to the Air Festival unless they have a ticket.
“The Duxford Air Festival is advance tickets only. Anyone without a ticket should not attempt to travel to the event as they will not be able to gain entry.”
The agency added that motorists not going to the show should also expect congestion.
The statement said: “Anyone travelling through the area is advised to allow extra time for their journey or to plan an alternative route or time. If you are travelling to the Air Festival, please follow the AA signs rather than your own sat nav.
“Although there won’t be any road closures, the M11 at junction 10 is expected to be busier than usual throughout the weekend.”
Highways England provides live traffic information via its website, iPhone app, local radio travel bulletins and electronic road signs.
Travel information is also available by phone from the Customer Contact Centre on 0300 123 5000 and via Twitter, @HighwaysEAST.
More information about the air show is available on the IWM DUxford website