Merrion Gates, right on the border between Dublin City and the borough of Dun Laoghaire-Rathdown. Once there were gates on the road, separating Dublin from the coastal territory to the south. Area which was once directly served by train – “Merrion” railway station opened in 1835 and closed in 1935.
Cross the road from the old train station once stood Merrion Castle, in the grounds of what is now St Mary's School for the Visually Impaired.
Nowadays this location makes it to the news mainly for truck damaging the level crossing.
Link to historic map available here.
Cache is small, but can hold small travel bugs or geocoins.
Source: wikipedia, archiseek.com