Ages: Sir Donald, 70 yrs. Ronald, 78 yrs.
'Foolish' Idea: Buying up wasteland for car parks.
How Idea was Launched:
In 1948, Sir Donald and Ronald, formed the holding company, National Parking Corporation, for the National Car Parks chain.
Built from the humblest of beginnings - from buying wasteland and charging a fee in return for car parking spaces, to the huge multi-stories concrete National Car Parks present in most towns and cities.
NCP is now Britain's biggest car park company.
Earnings: The holding company, National Parking Corporation was sold in 1998 for £801million.