Following the death of Harry Wellband, a highly successful Otford farmer and agricultural contractor, Castle Farm was sold in 1933.
At this time a projected replacement for London’s Croydon Airport was planned to be built nearby, between Eynsford and Swanley. This would have generated as much industry and housing as Gatwick later did for Crawley and Horley. The farm, including all the ruins, was purchased by William Blount Collier, a local builder, who sold on the farmhouse with a dozen acres to Eric MacDowall, Borough Engineer of Westminster, who modernised it as a family home and renamed it ‘Castle House’. The remainder of the land was scheduled for development by Collier who was joined by Alfred Waite, founder of Waites Garage (now Beadles). Their partnership was intended to develop the southern part of Otford, though fortunately for the village their plans were thwarted by the Second World War and subsequent planning legislation.
This ‘threat’ to the Otford Parish Council by the new owner, set out that unless arrangements were put in hand speedily to purchase it for the community, he would be ‘forced’ to surround it with suburban houses.
Local people were scandalised at the prospect, and a campaign to save it was initiated. A conference held in the village was chaired by the Bishop of Rochester, and in 1935 an appeal led by the Archbishop of Canterbury, Dr. Cosmo Gordon Lang, resulted in emergency repairs to the fabric, and in 1937 the land and buildings were purchased by subscription raised in several dioceses, and subsequently conveyed to the archbishops of Canterbury to be held in perpetual memory of the events here. In 1937 the property was transferred to the old Sevenoaks Rural District Council, and has remained in the ownership of the local authority ever since.