My research has indicated clearly that the difficulty of access into Sutherland very much limited the number of visitors, well into the 19th century. The lack of infrastructure also delayed accurate mapping of the county. Where the Lothians, for example, were surveyed in some detail from the 1740s onwards, Sutherland had to wait until 1833 before a map was published that had resulted from a full survey. John Thomson's fine county atlas was a carefully prepared volume that contains a map of Sutherland which was "attested by" Frances Suther (Factor to the Countess of Sutherland), Major William Clunes, Gabriel Reid Esq., and Captain Donald Mackay, RN, for Lord Reay's Country. It is dated 1823. However, the first full survey of the county was commissioned from Gregory Burnett and William Scott by the Duke of Sutherland - a name one barely dares mention on account of his part in the Clearances. I do not doubt his ultimate responsibility for those violent and unfortunate events (though the Scotsmen James Loch and Patrick Sellar were those directly overseeing the process), but I think his work on the infrastructure within the county should be acknowledged - his road across the Moine, the Inns he erected to aid travellers, and this map which was surveyed in 1831 - 1832, and issued in 1833.
I do not have copies of all the maps listed in Moir's Early Maps of Scotland Vol II (1983), but I have a fair number and will add them to this photo-album page. Should you wish to consult them in more detail, I suspect the images on the excellent NLS website will be far better than mine, and I would recommend that you visit it, but I hope mine are better than nothing....
I shall devote another, separate page to Bryce's map of the North Coast (1744).