Apart from compact Puerto Williams and the even tinier fishing village of Puerto Toro, ISLA NAVARINO, the largish island to the south of Isla Grande, is an uninhabited wilderness studded with barren peaks and isolated valleys. Navarino is dominated by a dramatic range of peaks, the Cordón Dientes del Navarino through which weaves a 70km hiking trail called the Los Dientes Circuit. What has spoiled some of the landscape, especially the woodland, however, is the devastation brought about by feral beavers, imported from Canada for fur-farming in the 1940s by the Argentine military – a project that misfired most spectacularly and to which there is still no solution.