There are 3 islands Inis Mor (the largest island), Inis Meann and Inis Oirr (the smallest)
You will wonder at the large round ruins of the many forts and when you visit Dun Aengus you will be in awe at how these monuments were built. There are many thatched cottages and plenty of turf filled pubs for you to visit. While Inis Mor is probably the most visited island all three have there uniqueness, eg. Inis Mor has the ancient fort Dun Aengus, Inismaan has Tech Synge and Inis Oirr has the Plassey Shipwreck. All islands have ancient ruin forts which are well worth a visit.
The islands may be reached by;
Year-round ferry services exist and are passenger only, with no car ferry available. None presently operates from Galway Harbour, and only Aran Island Ferries operate a year round service from Rossaveal in County Galway, connected by a bus service from Galway city.
Ferries are available to the Aran Islands from Doolin in County Clare (Seasonal April 1–October 31).
Aer Arann Islands operate an air service from all three islands.See http://www.aerarannislands.ie/