Hirta

(from the article `Saint Kilda`) ...sea cliffs rising to 1,300 feet (400 metres) that support the world`s largest population of gannets. There are also distinctive species of sheep, ...
Found on http://www.britannica.com/eb/a-z/h/53

HIRTA

abbreviation: High intensity radio transmission area
Found on http://www.encyclo.co.uk/local/20021
No exact match found