This archaeological and historic landscape survey of the Trewithen Estate Registered Park and Garden was commissioned by Cookson and Tickner as part of a larger Conservation Management Plan for the Estate. A range of sources including historic documents, maps, aerial photographs and LiDAR data was consulted and a walkover survey was carried out. The report documents archaeological features identified within the survey area of the Trewithen Estate and makes recommendations for their future management. Trewithen is a parkland landscape which has evolved in more than 300 years in the ownership of one family. Although the footprint of the house has seen limited alteration, the gardens and parkland have evolved from the more symmetrical, linear forms of the early 18th century to the informal woodland gardens of the 19th century which have been added to in the 20th century and are now open to the public. Within the wider parkland changes can be observed in the addition and removal of boundaries, likely to be largely a result of a shift in arable cultivation methods during the 19th century. Some archaeological traces of earlier pleasure gardens survive, and supported by historical mapping provide an insight into the changing fashions of the time and tastes of the owners of Trewithen.