"We had heard a world of talk about the marvellous beauty of Lake Tahoe, and finally curiosity drove us thither to see it. Three or four members of the Brigade had been there and located some timber lands on its shores and stored up a quantity of provisions in their camp. We strapped a couple of blankets on our shoulders and took an axe apiece and started—for we intended to take up a wood ranch or so ourselves and become wealthy. We were on foot. The reader will find it advantageous to go horseback. We were told that the distance was eleven miles. We tramped a long time on level ground, and then toiled laboriously up a mountain about a thousand miles high and looked over. No lake there. We descended on the other side, crossed the valley and toiled up another mountain three or four thousand miles high, apparently, and looked over again. No lake yet. We sat down tired and perspiring, and hired a couple of Chinamen to curse those people who had beguiled us. Thus refreshed, we presently resumed the march with renewed vigor and determination. We plodded on, two or three hours longer, and at last the Lake burst upon us—a noble sheet of blue water lifted six thousand three hundred feet above the level of the sea, and walled in by a rim of snow-clad mountain peaks that towered aloft full three thousand feet higher still! It was a vast oval, and one would have to use up eighty or a hundred good miles in traveling around it. As it lay there with the shadows of the mountains brilliantly photographed upon its still surface I thought it must surely be the fairest picture the whole earth affords."

"So singularly clear was the water, that where it was only twenty or thirty feet deep the bottom was so perfectly distinct that the boat seemed floating in the air! Yes, where it was even eighty feet deep. Every little pebble was distinct, every speckled trout, every hand’s- breadth of sand. Often, as we lay on our faces, a granite boulder, as large as a village church, would start out of the bottom apparently, and seem climbing up rapidly to the surface, till presently it threatened to touch our faces, and we could not resist the impulse to seize an oar and avert the danger. But the boat would float on, and the boulder descend again, and then we could see that when we had been exactly above it, it must still have been twenty or thirty feet below the surface. Down through the transparency of these great depths, the water was not merely transparent, but dazzlingly, brilliantly so. All objects seen through it had a bright, strong vividness, not only of outline, but of every minute detail, which they would not have had when seen simply through the same depth of atmosphere. So empty and airy did all spaces seem below us, and so strong was the sense of floating high aloft in mid-nothingness, that we called these boat-excursions “balloon-voyages.”" (Roughing It)

See Wikipedia