If you want to see many different examples of the celtic cross then Glasnevin Cemetery is the place to go.

In Ireland, it is a popular legend that the Celtic Catholic cross was introduced by Saint Patrick or Saint Declan during his time converting the pagan Irish, though no examples survive from this early period. It has often been claimed that Patrick combined the symbol of Christianity with the sun cross, to give pagan followers an idea of the importance of the cross by linking it with the idea of the life-giving properties of the sun. However this theory is now thought unlikely by most art historians, who think an origin from crosses carrying a victor's wreath around their intersection is more likely.

The earliest versions of the cross were carved onto slabs that laid flat on the ground and were called Recumbent cross-slabs. But, they gradually evolved into carvings on upright slabs (Erect cross-slab), sometimes depicted with a slightly rounded top. Both versions are always decorated intricately with typical Celtic patterns; spirals, knot work, foliage, keys, Biblical tales and animals.

The most recent evolution of the Celtic cross's depiction is a free standing, statuesque Celtic cross, rather than being simply a carving on a slab. The cross was effectively now "freed" from the stone, so these versions are known as Freestanding crosses. And the arms of the cross were made longer, so they extended the circle, with the inner shapes between the arms and the circle being cut away. And this cross is most commonly seen in the form of gravestones in Irish churchyards or as war memorials all over Britain.

The Celtic Revival of the mid-19th century led to an increased use and creation of Celtic crosses in Ireland. In 1853 casts of several historical high crosses were exhibited to interested crowds at the Dublin Industrial Exhibition. In 1857, Henry O'Neill published Illustrations of the Most Interesting of the Sculptured Crosses of Ancient Ireland. These two events stimulated interest in the Celtic cross as a symbol for a renewed sense of heritage within Ireland.