The land surrounding Kingston Lacy was registered as being of special historic interest in the Register of Historic Parks and Gardens in 1986, it being "parkland developed in the seventeenth, late eighteenth, and nineteenth centuries, together with late nineteenth-century formal gardens and informal pleasure grounds." The estate comprises about of parkland and other ornamental land and about of gardens. The site slopes gently towards the southwest and includes the summit of the Iron Age hillfort of Badbury Rings towards its northwest extremity, and within the estate is part of the Roman road from Dorchester to Old Sarum.