Wandering the lanes with their ivy-covered stone walls is the best way to experience the island. There are two, circular waymarked National Looped Trails, one of 8km, one of 13km.
Walking Inisheer's Shore
As well as the island's two official, circular trails, you can also circumnavigate Inisheer's 12km shoreline in about five hours, gaining a far deeper understanding of the island than from hurried visits to the main sights.
From the Inisheer ferry pier, walk west along the narrow road parallel to the shore and go straight on to the small fishing pier at the northwest corner of the island. Continue along the road with the shingle shore on one side and a dense patchwork of fields, enclosed by the ubiquitous stone walls, on the other. Look for tide pools and grey seals resting in the sun.
About 1km from the acute junction, turn left at the painted sign; about 100m along the paved lane is the Well of Enda.
Continue southwest as the path becomes a rough track. After about 600m, head roughly south across the limestone pavement and strips of grass to the shore. Follow the gently sloping rock platform around the southwestern headland (Ceann na Faochnaí) and walk east to the lighthouse near Fardurris Point (two hours from the ferry pier).
Stay with the coast, turning northeast. You'll see the wreck of the Plassy in the distance. When necessary, use stiles to cross walls and fences around fields. Note that the grass you see grows on about 5cm of topsoil created by islanders who cleared rocks by hand and then stacked up seaweed over decades.
Head north, following the track, which then becomes a sealed road at the northern end of Lough More. Continue following the road along the northern shore of the island, past the airstrip.
At the airstrip you can diverge for Teampall Chaoimháin and O'Brien's Castle. Otherwise rest on the lovely sands of the curving beach and check out the nearby Cnoc Rathnaí, a Bronze Age burial mound (1500 BC) that is remarkably intact considering it was submerged by sand until the 19th century, when it was rediscovered.