Adrossan Farms and the Ardrossan Estate were once part of a 800 plus acre estate in Radnor Township, Delaware County. The estate was built by banker Robert Leaming Montgomery and features 50 room Georgian revival mansion designed by architect Horace Trombauer in 1911. Parts of Ardrossan have been subdivided over the years, and now the bulk of the estate is in the process of succumbing to this fate. The play and film The Philadelphia Story was inspired by the stories of the Montgomerys.
Part of the estate was, and still is for now, a working farm with cattle and hay and corn fields. The farm was also was set this section of Radnor Township apart from surrounding suburbia. It made travel along Darby Paoli Road a treat, rather than a chore.