The 17 first-class counties were joined by five Minor Counties: Bedfordshire, Buckinghamshire, Cornwall, Norfolk and Oxfordshire. Teams who won in the first round progressed to the second round. The winners in the second round then progressed to the quarter-final stage. Winners from the quarter-finals then progressed to the semi-finals from which the winners then went on to the final at Lord's which was held on 5 September 1970.