“If you don’t mind,” said Joachim, “I’d like to introduce you to the hermit. He and I will have a lot to discuss after that, but you might be interested in trying to find the wood nymph.”

We tied our horses’ reins to a branch and scrambled up a steep track at the side of the waterfall. At the top, the stream emerged from the dark shadow of a grove of trees. We continued along its edge, ducking our heads where the branches swung low. Here the water course widened into a swirling pool. In a few more yards, I saw what seemed to be a stone hut, like those we had seen further down the valley.

But I was more interested in the river. When Joachim had spoken of its source, I had visualized a spring where water gurgled up from the earth, and I was wondering how the river could carry so much water and so rapidly. I went a little further, with Joachim following, and then spotted the real source.

The river did not gurgle up from the earth but rather poured out of the face of the cliff. A cave mouth, only a few feet high but at least twenty feet broad, opened in the limestone, and the water boiled from it. A faint but steady wind accompanied the rushing river. After emerging and making a quick eddy under the branches of the grove, the water rushed over the edge of the falls and disappeared on down the valley.

“Has anyone ever gone into the cave to follow the river back further?” I asked. There seemed to be a low, damp ledge along one side of the river, along which it might be possible to walk or crawl.

“I don’t think so. The cave’s too small, and there’s too much water,” said Joachim absently. We walked back to the stone hut, and he went down on one knee before it, dropping his head reverently.