A simple multi to show you around the centre of Portrane
The 3 stages plus final are pretty close to each other so it shouldn't take you too long the find the cache. You need to find some numbers at the various stages, then do a quick calculation to get the final coordinates.
Stage 1
You find yourself at the St. Catherine's Church. Go into the ruins, find the gravestone of the Counihan family and look for the year Raymond died = 1AB2
Stage 2
Here you see the memorial for the RMS Tayleur, a ship which ran aground just off Lambay Island. On the memorial there is a plaque with a date on it = C1st January 18D4
Stage 3
Right next to the Anchor there is the Brook pub. Over the entrance you find a year = E8FG
Now you have everything you need to calculate the final: N 53° 29.(A-B) (A) (C) W 006° 06.(D) (F) (G-2xE)
Have fun and enjoy your short walk!