Slieve Gullion is popular with hillwalkers, with about 20,000 people climbing the hill every year. A road leads to a small carpark about halfway up the western side of the mountain. From there is a trail leading to the summit. There is also a waymarked trail from the northern side of the mountain. As there is no security on the mountainside, cars parked there are often broken into by thieves, and police have asked visitors not to leave valuables in cars.