The owners of Elizabethan Pitchford Hall in Shropshire are puzzled by dangerous sinkholes on the estate, possibly caused by an extraordinary subterranean Georgian bathhouse. In Dorset, American countess Julie Mapperton is hard at work restoring Mapperton House, and Brancepeth Castle opens its doors for the annual Dragon Quest, celebrating the legend of the infamous Lambton Worm.

At Treberfydd House in Bannau Brycheiniog (the Brecon Beacons), the biggest wedding of the year is underway, at least if the weather holds. In Shropshire, the owners of the Elizabethan Pitchford Hall are proud custodians of what is believed to be the world's oldest treehouse, supported by Britain's oldest broadleaf lime tree, which urgently needs some restoration work.