BBC Sport - The Valleys Fighter: Why do the valleys produce such great boxers?

The Valleys Fighter: Boxing champions

As part of BBC Cymru Wales​' ‪Real Valleys‬ season, we bring you a special documentary as Liam Williams, a young boxer from Clydach Vale, follows in the footsteps of legendary fighters and heads towards his first professional title.

The south Wales valleys have churned out champion after champion, giving the nation the likes of Howard Winstone, Johnny Owen and Joe Calzaghe.

But why are the valleys such a hotbed for boxing?

Here is a little taster of what you can expect from The Valleys Fighter, which airs on BBC One Wales at 10.45pm on Monday, 30 March.