A low-lying, flat-topped basalt island situated about 18 km west of the mainland Dyfed coast. Vegetation is limited by exposure to wind, salt spray and the large numbers of seabirds. The site is important for its seabird colonies, including a very large gannetry.
BirdLife International (2023) Important Bird Areas factsheet: Grassholm. Downloaded from
http://www.birdlife.org on 30/03/2023.