The Llac de Puigcerdà is a small artificial lake at the north end of town, fringed with mature plane trees and lined with belle-époque summer mansions built by the Catalan bourgeoisie at the end of the nineteenth century. The Café del Llac on the south shore is the traditional spot for a vermouth before lunch.
A path circles the lake — twenty minutes at a wander — and rowboats can be rented in summer. In winter the lake sometimes freezes hard enough for skating. The mansions, with their turrets, glazed verandas and elaborate gardens, give the lakeside a faintly Alpine air, more in tune with the resort culture of the late nineteenth century than with the medieval town a few streets away.