When it’s warm, one the best free things to do in St. Moritz is to take a restful walk around the shore of the resort’s own lake.The trail is five kilometres or so, and takes between one and two hours.It all depends on how often you stop to photograph the greenery, Alpine wildflowers, dark forest and brooding peaks like the 3,000-metre Piz Rosatsch.Although the water might be a little chilly for swimming, you can still hire a stand-up paddleboard or canoe and take a self-guided trip over the lake.When the lake freezes in winter, the surface is used for polo, and three weekends of horseracing are scheduled every February.