I pulled my former colleague AT up the muddy bank to the gap in the wall that led to the open countryside. At first I thought that it was too small to accommodate us, but GB demonstrated that the space expanded to allow cyclists to pass their bikes through, so there was plenty of room.

Even so AT was a bit nervous, and concerned that he would rip his clothes.

‘Do you think anyone would object if I take my trousers off?’ he asked.

As he undressed I discovered that – rather than conventional underwear – beneath his trousers AT wore a loose two-legged green sarong.