Just to add a bit of local... there's 2 farms called North and West Tarwathie just beside and west of Mormond Hill, on the A981 road about 6 miles south from Fraserburgh (pass them on my way to work every day!) which are more likely to be referred to in the song than a place over near Buckie. Mormond Hill lies between Tarwathie and the village of Strichen, and Crimond (there used to be a coffin road ran around the southern side of the hill). Bit a of nautical saying - 'Keep Mormond Hill a handspike high, and Rattray Briggs you'll nae come nigh' - good gen, as there were a lot of shipwrecks off Rattray.

cheers
madwaff