Road users travelling M1 northbound are advised to follow the hollow diamond diversion symbol on road signs:
Exit the M1 at J6, at the end of the M1 exit slip turn left on to the A405 'North Orbital Road' Continue travelling on the A405 until 'Park Street Roundabout' Take the 1st exit on to the A414 Rejoin the M1 at J8Road users travelling M25 anti-clockwise are advised to follow the hollow square diversion symbol on road signs:
Exit the M25 at J21A and take the first exit onto the A405 At "Leavesden Green" junction, take the second exit onto the A41 towards the M25. At "Hunton Bridge" roundabout, take the second exit to re-join the M25 at J19Road users travelling M25 clockwise are advised to follow the hollow triangle diversion symbol on road signs:
Exit the M25 at J20 and take the fourth exit onto the A41. At A41/A411 "Hunton Bridge" roundabout, take the first exit to continue on the A41. At A41/A405 "Levesden Green" junction, take the exit onto the A405 towards St Albans. Continue to re-join the M25 at J21A.
