It was called Five Fingers Mountain, and from the name you can imagine how it was shaped – like the five fingers of a hand standing up from the plain. In between the peaks there were four valleys. The first valley was the nearest to the county seat, which was maybe only two or three kilometres from the mountain. There was a little village here, the houses clustered along the mountainside. Given that this valley was the broadest, the housing compounds for Unit 701 had been constructed here, together with a hospital, school, shops, restaurants, guest house, playing field and so on. It was a complete little community, and although getting to meet the people there was a bit more complicated than usual, it was not that difficult to be able to come and go. Later on, when I was writing this book, I came to visit quite regularly and would stay at the guest house for days at a time. After a few such visits lots of people recognized me and since I always wore sunglasses (since the age of twenty-three, thanks to a condition that makes my right eye unusually sensitive to sunlight, I have always worn sunglasses when I am out of doors), everyone called me Specs.

The remaining three mountain valleys were much narrower and the difficulties of getting in increased the further you went. I was lucky enough to be able to visit the second valley three times and the third valley twice. The fourth and furthest valley I was never allowed to set foot in. My understanding is that this valley is where the cryptography unit was situated and that was the most security-sensitive area in the whole mountain. The covert operations division was based on the right-hand side of the second valley, with the training centre on the left; the bosses of both work units held the rank of deputy bureau chief. These two work units spread across the valley like a pair of wings, but the left-hand side was clearly much bigger than the right. Usually there were not many people from the covert operations division in residence, since they were all out in the field.

There were also two work units in the second valley: one was the intercepts division and the other the head office of Unit 701. The layout of these two work units was different from that of the covert operations division and the training centre, which had been built face-to-face, in that they had been built in a row – the head office of Unit 701 came first, then the intercepts division. The two work units shared the space between them, where they had put in a soccer pitch, a dining hall, a little clinic and so on.