Black lines on the Komoot map are always a gamble when riding your bike in Sweden, but this one is definitely worth while! If you follow the 'Surtesjön runt' sings, the path wil bring you round the Surtesjön lake via a beautiful hardpack gravel path, only used by the occasional hiker.
The path is rolling and winding and gives multiple beautiful views upon the lake and it's surroundings. A definite must-ride with the gravel bike.