The entrance was agreeable enough, the passage being near half a mile broad. On the left hand was a small river, whose channel was deep, but the water shallow, there having been but little rain for some time; the water ran very rapid, and, as my Spaniard told me, was sometimes exceeding fierce. The entrance lay inclining a little south, and was so straight, that we could see near a mile before us; but the prodigious height of the hills on both sides, and before us, appearing one over another, gave such a prospect of horror, that I confess it was frightful at first to look on the stupendous altitude of the rocks; everything above us looking one higher than another was amazing; and to see how in some places they hung over the river, and over the passage, it created a dread of being overwhelmed with them. The rocks and precipices of the Andes, on our right hand, had here and there vast cliffs and entrances, which looked as if they had been different thoroughfares; but, when we came to look full into them, we could see no passage at the farther end, and that they went off in slopes, and with gulleys made by the water, which, in hasty rains, came pouring down from the hills, and which, at a distance, made such noises as it is impossible to conceive, unless by having seen and heard the like before; for the water, falling from a height twenty times as high as our own Monument, and, perhaps, much higher, and meeting in the passage with many dashes and interruptions, it is impossible to describe how the sound, crossing and interfering, mingled itself, and the several noises sunk one into another, increasing the whole, as the many waters joining increased the main stream. We entered this passage about two miles the first night; after the first length, which as I said, held about three quarters of a mile, we turned away to the south, short on the right hand; the river leaving us, seemed to come through a very narrow but deep hollow of the mountains, where there was little more breadth at the bottom than the channel took up, though the rocks inclined backward as they ascended, as placed in several stages, though all horrid and irregular; and we could see nothing but blackness and terror all the way. I was glad our passage did not turn on that side, but wondered that we should leave the river, and the more when I found, that in the way we went, having first mounted gently a green pleasant slope, it declined again, and we saw a new rivulet begin in the middle, and the water running south-east or thereabouts. This discovery made me ask if the water went away into the new world beyond the hills? My patron smiled, and said, No seignior, not yet; we shall meet with the other river again very quickly; and so we found it again the next morning.