Cerro Castillo's basalt spires are the crowning centerpiece of Parque Nacional Cerro Castillo, a sprawling 1800-sq-km park located 75km south of Coyhaique. It earned national-park status only in 2017, though park infrastructure has yet to catch up, and the most-used access points remain private property. The park boasts fine hiking in southern beech forest and open high-alpine terrain. Its namesake, the 2700m triple-tier Cerro Castillo, is flanked by three major glaciers on its southern slopes.
Hikers can complete a segment of Sendero de Chile with the 16km trail to Campamento Neozelandés. A recommended four-day Cerro Castillo Circuit trek leaves from Carretera Austral Km75, at the north end of the park, and winds around the peak via a high route passing glaciers, rivers and lakes to end in Villa Cerro Castillo. It's also serious, remote backcountry. Before heading out, share your plans with others and check in with the ranger to avoid seasonal hazards.