Wikipedia
A/S Graakalbanen was a private company that built and operated the Gråkallen Line of the Trondheim Tramway between 1924 and 1972. Established in 1916, it bought large land areas in Byåsen, and built a tramway through these to reach the recreational areas in Bymarka. The line first reached Munkvoll in 1924, Ugla in 1925, and finally Lian in 1933. The company owned through its history seven trams and five trailers, and only in the last few years did it operate six borrowed TS Class 7 trams.
The company had financial difficulties throughout its life. Only in the 1940s and 50s was traffic sufficient to create a profit. To supplement, the company was a large land owner, and sold housing lots along the line to increase ridership and generate income. It also operated sales of ice, and the recreational area at Lian. The company was bought by the city in 1966, and merged with Trondheim Sporvei and Bynesruten in 1972 to form Trondheim Trafikkselskap.