Read more about the Great Famine at the history place.
The cross shown is based on the early wheel cross from Celtic art, but extended beyond the wheel into what is known as a Latin cross, similar to the one found at St. Edrens, Ireland, according to "Symbolism of the Celtic Cross" by Derek Bryce. Here's a good video explaining the Irish Famine.
Nearby to this monument is a campground. The beach is stony, but good for walking and watching birds.