Rather flat, somewhat barren with small fields surrounded by stone walls and narrow paved roads. It is the largest of the 3 Aran Islands & can be reached by plane or boat from the mainland. Main things to do there are hire a bike and cycle the island. As long as there aren't any strong on shore winds it is easy enough.
Of course a visit to the promontory fort of Dun Aengus, on the edge of a high cliff, is a must. http://en.wikipedia.org/wiki/D%C3%BAn_Aengus
Kilronan is the town on it and during the high season there should be some action going on, perhaps traditional music, not sure about restaurants.
I think there is a small musemn on the island.
Walking, chilling out, admiring the scenery, getting to meet the locals & learning a few words of Gaelic since this is one of the shrinking Gaeltacht areas left in Ireland, good conversation. Experiencing the island culture. Perhaps visiting the other two islands, Inisheer and Inishmann. This can be done by aircraft, not sure by boat & not sure if a return trip can be done by day or you could just head back to the mainland from one of these islands since the aircraft lands on all 3 of them. Flying is exciting since you land on grass strips in tiny airports and on the way back to the mainland you should be able to see the Cliffs of Moher. Try & bags the co pilots seat for extra measure, I did. :) about 7 years ago