Hand Tools Under River
You can chip away at a mountainside with an axe and a shovel because the hard, dense rock can support itself, but these tools won't do you much good here. The ground beneath this river is loose and wet. It will fall on top of you, and water will pour in if you try to dig a tunnel through it. You'll have to find a way to support this soppy ground if you want to build a tunnel here! Try again!