The main hiking trail on Nólsoy runs south from the village all the way to the lighthouse at Borðan on the island's southern tip — roughly five hours return over the island's backbone. The path climbs over Eggjarklettur (372 metres), crosses high moorland patrolled by Arctic terns and skuas, and descends to the lighthouse perched on the cliff edge above the open Atlantic. The terrain is genuine mountain walking: grassy and boggy in places, rocky in others, with sections that require careful footing in wet conditions.
The views along the route are reason enough to make the effort. To the west, Streymoy and the buildings of Tórshavn catch the light across the sound. To the east, nothing but sea until Iceland. The lighthouse itself is automated and unmanned, but the location — alone on its headland with the Atlantic swells breaking against the rocks below — is spectacular.
Wear proper boots, carry food and water, and check the weather before setting out. Faroese weather can change dramatically in an hour, and the ridge is exposed. The trail is marked with cairns and generally well-defined. Allow five hours for the full round trip from the village; the ferry schedule should dictate your departure time.