After running 3242km from Buenos Aires, RN 3 reaches its terminus at the shores of Bahía Lapataia. From here, trails Mirador Lapataia (500m), with excellent views, and Senda Del Turbal (400m) lead through winding lenga forest further into the bay. Other short walks include the self-guided nature trail Senda Laguna Negra (950m), through peat bogs, and the Senda Castorera (400m), showcasing massive abandoned beaver dams on a few ponds.
Senda Hito XXIV
At the end of the road to Lago Roca, a flat trail (a 10km four-hour round-trip) leads around Lago Roca’s forested northeast shore to Hito XXIV – veinticuatro in Spanish – the boundary post that marks the Argentina–Chile frontier. It is illegal to cross the frontier, which is patrolled regularly.
From the same trailhead you can reach Cerro Guanaco (973m) via the steep and difficult 8km trail of the same name; it’s a long, uphill haul, but the views are excellent.
This 8km (four-hour) trek leads west from Bahía Ensenada along the coastline. Keep an eye out for old conchales (archaeologically important mounds of shells left by Yahgan inhabitants), now covered in grass. The trail meets RN 3 a short way east of the park administration (guardería) center at Lapataia. From here it is 1.2km further to Senda Hito XXIV.
It might be tempting to roll up the cuffs and go clamming, but be aware that occasional marea roja (red tides) contaminate mollusks (such as clams and mussels) along the shore of the Beagle Channel. This seasonal trail opens in December.
Senda Pampa Alta
The low heights of Pampa Alta (around 315m) grant long views across the Beagle Channel to Isla Navarino and Isla Hoste. RN 3 meets the trailhead 1.5km west of the Río Pipo and Bahía Ensenada road turnoffs (3km from the entrance gate). The 5km roundtrip trail first climbs a hill, passing a beaver dam along the way. Enjoy the impressive views at the lookout. A quick 300m further leads to a trail paralleling the Río Pipo and some waterfalls.
From the road 2km southwest of Lapataia, a trail leads north along the western side of Río Lapataia to a fishing spot opposite Isla El Salmón. Laguna Negra, a lovely lake in the forest, is easily accessible via a 1km circuit loop.
This 4km (three-hour) roundtrip trek from Bahía Ensenada follows a path eastward past an old copper mine to the popular rock-climbing wall of Palestra, near a refugio (rustic shelter) that is no longer in use.