The Round Tower is a Grade II Listed folly, which had been reduced to ruin by years of neglect and fire. Located on the crest of a hill, the exposed site is visually integral to the setting of this listed structure. The design approach maintains the open relationship with the surrounding agricultural landscape by developing a discreet and substantial underground extension to the tower. Housing the main open plan living spaces, this extension is lit by a central open sunken courtyard and a lateral ‘landscape scoop’ concealing the new swimming pool and associated sun terraces from public view. Galvanised metal railings protect the sunken courtyard and landscape cut are the only publicly visible clues of the modern rehabilitation of the tower. Natural local materials were chosen to match the existing setting, with Cotswold limestone rubble wall lining used to draw the landscape into the subterranean extension blurring the indoor/outdoor relationship. The tower clearly remains the dominant structure, providing the front door to the four-bedroom family house, a means of vertical circulation, additional accommodation and a roof terrace for the enjoyment of the panoramic views of the surrounding landscape.