In theory, access is prohibited. You may not believe me, but our entry was in fact entirely accidental. We were following paths and roads that encircled the fence, replete with warning signs, but at some point found ourselves inside the complex. We did not jump a fence, or scramble through a hole. We just walked and chatted. When we eventually got down to the main gate, we found ourselves in an awkward position. We were inside, and the fencing was quite secure in this part. We found a weakness in the chainlinks nearby, and we had to scramble through to get out.