Ross-shire, like Sutherland was difficult of access well into the 19th Century. Once the railway line from Inverness to Lochalsh was opened in 1870, the station at Achnasheen gave access to places like Loch Maree. Queen Victoria visited the loch in 1877, thereby increasing its popularity as a tourist destination. Photographs of the accessible areas are not exceedingly rare, but still much of the county was difficult to reach until the advent of the car.
I shall also post an album page of postcard images of the county.