It opened on 2 November 1959 . This included two of the motorway 's spurs , the M10 at Junction 7 , and the M45 at Junction 17 . The first section of the motorway opened between junction 5 ( Watford ) and junction 18 ( Crick\/Rugby ) on 2 November 1959 together with the motorway 's two spurs , the M10 ( from junction 7 to south of St Albans originally connecting to the A1 ) and the M45 ( from junction 17 to the A45 and Coventry ) .