Cover the old Ard Rí Hotel (on top of the hill overlooking Waterford City) with a big Three Sisters 2020 banner. A very iconic building put to good use! Everyone can then ‘look upto’ the three sisters. Great public awareness potential.
Separately, you could paint the Three Sisters 2020 logo on the mountain side where you would often see the Waterford, Kilkenny and Irish flags! (Above the train Station in Waterford)