The Strawbridges appreciated both the historical significance of Graeme Park and what we now call the Penrose Strawbridge Farm. In the 1950s they were forced to sell some of the property to extend the runways at the Willow Grove Naval Air Station and were afraid that the air base may eventually take all the property, so in 1958 they sold, for $1, 42 acres including the Keith House to the Commonwealth of PA to ensure that the historic Keith House would continue to be preserved.
After Mr Strawbridge's death in 1968, Mrs Strawbridge decided to preserve the rest of the estate and sold a 1/2 interest in the remaining acreage to the Natural Lands Trust for $1, with the remain 1/2 interest going to the Trust upon her death. When she died in 1996, the Trust took title to the property which it wanted to preserve as open space. It was not equipped, however, to restore or care for the buildings. Horsham Township did want to preserve the buildings so The Trust sold the 102 acres property to the Township.
"According to the terms of the sale, roughly 60 acres between Governor Road and County Line Road can only be used for passive recreation and its use must be compatible with the use of Graeme Park. The Township can develop the remaining 30+ acres, and the house and 10 acres around it can be sold." (41 p5.2
Per this agreement, the Township did put the 10 acres and buildings out for bid. HPHA and HPPI won this bid and entered into a lease with the township in 2003.