The Mourne Mountain range in County Down is one of three highland areas in Northern Ireland.
These mountains are made of granite. Granite is an igneous rock which is formed from molten rock. This molten rock called magma cooled under the earth's surface to form rocks with large crystals.
Many of the high peaks in the Mournes have granite tors at their summits. This is Slieve Bearnagh and you can clearly see the granite tors.
Soils in this area are thin and poor so there is not a lot of vegetation and quite large areas of bare rock. Mountain areas like the Mournes are also colder and wetter than the surrounding lowland and there is very little economic activity or settlement.
One of the few economic activities in the Mournes is the supply of water. Reservoirs like Ben Crom and the Silent Valley supply water for Belfast. The Mournes, with their steep sided valleys and high rainfall make them an ideal site for collecting water.
At the top of Slieve Commedagh there is evidence of another economic activity - quarrying.
There are many quarries in the Mournes but like this one they are no longer used. At one time they supplied granite for the streets, buildings and cemeteries of Northern Ireland. They also supplied stone for the Mourne Wall which you can see here running across the top of Commedagh. 
The wall was built by the water Commissioners in the last century to surround the area used to collect water for the reservoirs.
The wall continues onto the slopes of Slieve Donard. This is the highest mountain in Northern Ireland at 852m.
From the top of Donard there is a view over Newcastle which shows three further uses for the Mournes.
The main economic use is leisure, recreation and tourism. The scenic views of the Mournes attract visitors from around the world. Newcastle, at the foot of Slieve Donard, has developed as a base for climbers and hill walkers.
Another economic activity is forestry, trees can be grown in sheltered areas like the Glen River valley. Farming is also possible on the lower slopes.
The Mourne Mountains are made of Granite. Granite is an Igneous rock formed from Magma which has cooled under the earth's surface.
Economic activity and settlement is limited in this area because the soil is poor and the weather cold and wet.
The Mournes, with their steep sided valleys and high rainfall make them an ideal site for collecting water in reservoirs.
The main economic activity in this area is recreation and tourism. Forestry and farming can also be found on the lower slopes.