Gråkallen is a mountain in the Bymarka area in the municipality of Trondheim in Sør-Trøndelag county, Norway. The 552-metre (1,811 ft) tall mountain is located in the Byåsen part of the city of Trondheim.
The summit is covered by an abandoned fenced military installation. Below the summit (on the cole to the right of the summit above the lake) there is a ski station where buses from Trondheim will set you down. In the summer, the ski runs through the pine forests make for perfect hiking and mountain biking back to the city below.
The first element is grå which means "grey" and the last element is the finite form of kall which means "old man". (It is common in Norway to compare mountains with old men.)