Dún Aonghasa
Dun Aengus is a prehistoric fortress dating back to 1000 BC, perched on the edge of a 100m cliff plunging straight into the Atlantic Ocean. It's also Inir Mór's best-known attraction, and regularly inundated by tour groups. However, there are plenty of other ancient forts on the island, and the only feature unique to this one is its cheveaux de frise, an area of upturned rocks similar to defenses used by the Friseans to defend against cavalry charges. All visitors must disembark at the visitor centre and hike the remaining 1 km up the hill to the fort, and there is no guard rail at the cliff edge, so this may not be the best place to bring small children. Admission €2/1 adult/student.Dún Dúchathair
The Black Fort, a walled enclosure surrounded on three sides by cliffs with intricate designs in the stonework. This, more than any of the others on Inis Mór, raises the question of whether its use was defensive or ceremonial. When you get off the ferry most tourists head straight for Dún Aengus, which makes the Black Fort a much more enjoyable experience.There are two other stone forts on the island, Dún Eochla, is made up of two almost perfectly circular walls standing at the highest point on the island. You'll have to hike through some fields to get up to it. The final fort is Dún Eoghanachta, located south of the main road near Sruthán, most interesting for the remains of the clocháin dry-stone, beehive huts that it encloses.
Na Poill Seideáin
The Puffing Holes are two large, circular holes about 100 yards from the cliff edge, where the sea water will "puff" up through frequently as waves crash into a cave beneath the cliffs.Na Seacht dTeampaill
The Seven Churches is an ancient monastic site, with two churches and several out buildings. The Aran Islands have long drawn religious people seeking solitude and isolation.Poll Na bPéist
The Serpent Hole is a perfectly rectangular shaped pool, located near the village of Gort na gCapall, which is connected to the Atlantic by an underground channel.Bike out to the far end of the island for a view of the lightouse, wild waves and barren rocks.
