Located on the North side of Brackla Ridge, locally known as the "8 x's", the 7 massive underground magazine storage tunnels complete with platform were cut deep into Brackla Hill. Guarded by pill boxes overlooking the hill, they would protect the high explosives held within.

Today, numbers 1 and 2 have been filled in, only their vent shafts remaining and a little concrete, 3 and 4 being maintained to this day and were chosen as the headquarters for the Welsh RGHQ in time of nuclear war,  numbers 5, 6 and 7 are filled in but with a lot of evidence still remaining and still kind of accesible.

Later on during the war, and eighth tunnel was constructed from the Waterton site to the magazine complex, but the complex was not connected underground.Each tunnel led into a huge chamber sub divided into 8 smaller magazines separated by a 10 ft wall. The chambers run into Brackla hill nearly 150ft, whilst each chamber is approx 120ft wide.