How far down would you have to dig before you came to the centre of the Earth? And what would you find along the way? BBC Future descends into the depths.

This is part of BBC Future’s “Best of 2015” list, our greatest hits of the year. Browse the full list.

Much of our planet is hidden from view. The oceans – and especially the very ground we stand on – stretch for miles beneath us.

How far down do they go? How deep is the deepest part of the ocean, and what would we find along the way there? And back on dry land, we discover what makes up the solid ground beneath us, and how far we would have to dig to reach the planet’s core.

What have we missed? What else would you have liked to have seen in this graphic? Let us know on our Facebook or Google+ page, or message us on Twitter.