Behind the waterfall, everything was shrouded in shadow, but there was still more than enough light to see the scale of the wall. Like the ceremonial buildings at the heart of Paititi, it was built from exactingly carved blocks, fitted together with incredible precision. Thirty feet above him was its top, a horizontal line bisecting what had once been an irregularly shaped cave mouth. He couldn’t help thinking it looked like a battlement, the almost sheer, incredibly smooth surface making it impossible for anyone to get inside. Except by the entrance further along the ledge. The laser rangefinder had been correct; there was a second, much smaller hole. He regarded it with deep suspicion. It was about five feet high by four wide, and as far as he could tell wasn’t barricaded. A simple, inviting way in. Too simple. Too inviting. The Incas wouldn’t have built a massive defensive wall, then left a hole through which any gold-hunter could wander. There had to be a catch. ‘What do you mean, a wall?’ said Nina over the radio.
