Fresh Water at the Bottom

The last part of the staircase is different. The rock is not dry any more. It gets darker and colder under her feet. There is a smell of wet stone. At the bottom there is a low cave, and light from the water moves across its roof.

And there, right next to the sea, fresh water is coming out of the rock. Polly tastes it. It is cold and sweet. It should not be there. And it is the reason for everything above her.

This is how it works. The land on top of the cliff is limestone. Rain does not run off limestone. It sinks into it. The water finds small cracks and travels down inside the stone. Fresh water is lighter than sea water, so it can come all the way down to the bottom of the cliff and still be fresh when it arrives.

Now the staircase makes sense. Not soldiers, and not one night. It was probably monks, cutting down slowly for years to reach this water. A town on a cliff can have high walls and a great view and still have nothing to drink.