Skarðsdalur is the ski area above Siglufjörður, set in a steep valley a short drive from town. It is small by Alpine standards, but the setting is pure North Iceland: open snowfields, dark mountains, and the fjord never far from view.
In winter it gives Siglufjörður a second reason to stay overnight. Outside the ski season, the same valley is useful for getting a quick feel for the terrain that hems the town in.