As described in other members comments there is a short and easy way to climb Butter Mt. There is however a more rewarding alternative route which follows part of the Mourne Way. Starting at the Blue Quarry (Ott Track) car park J280 279 D the route is fully described in the WalkNI web site and in an illustrated booklet which can be requested on line. There are fine views NE to the high Mournes and, as the walk follows the wide U shaped ridge on the top of Butter Mt and turns SW Cock and Hen Mts in the Western Mournes and Slieve Gullion in Armagh come into view. On reaching the Spelga Pass road J260280 E turn left and at the T junction left again to walk back to the start. If you have two cars leave one at the Spelga Dam Car Park and avoid the road walk back. Linkback: https://mountainviews.ie/summit/458/comment/4063/