the stuff that's left behind after extraction and processing.

And these days, the mining company should be required to deal with those byproducts,

but in the past they often just piled them up

and assumed someone would deal with the problem

at some point in the future.

If those byproducts are toxic, that's a problem.

But here in Hirschau, in Germany, it's a bit different.

Just over there is an open-pit kaolin mine:

kaolin is a really common mineral

that's used in the manufacture of a lot of things,

everything from pottery to toothpaste.

And there is a big pile of mining byproduct here.

I'm standing on it, it is 120 metres high.

But it's just sand. Regular sand. Made of quartz,

like what you'd find in the desert.

Quartz sand can be useful in industry.

These days the sand that the mines produce here is sold off.

But for decades there was too much of it,

so as it was pretty harmless, the mining companies just piled it up.

What do you do with 35 million tons of sand, in a pile that's dominating the landscape?

The answer, of course, is make it a tourist attraction.

Welcome to the ski resort and amusement park of Mount Kaolino.

I should point out — it's 9am on a weekday as I'm filming this,

so there aren't many people around, it's not fully open.

In the summer school holidays,

this place is as busy as a regular ski slope would be in high season.

IN GERMAN:

A lot of this hill is covered in trees and other vegetation,

and they will help anchor the sand and keep everything in place.

So I had to ask:

surely all the people descending this mountain

keep dragging the sand down with them?

I'm sure that the local government could have insisted

that this hill be cleaned up and the sand disposed of somehow.

But why would they? Now, Hirschau isn't just a mining town.

It's a mining town with a local theme park.

Tourists have a reason to come here, and spend money.

There are more jobs for the locals.

And every so often, someone will come along and tell the world that, hey,

there's a ski slope made of sand in Germany.

No, I...

I can't sandboard, I would die.

This is not the hill to learn on!

I'm going to take the little cable car down.

How do I... I'm genuinely terrified I'm going to slip off this!

How do I get out of this?

That tightened it! Oh my god, okay.