Hopefully available to all in the UK at least.

BBC iPlayer - Wales at the Somme: Gareth Thomas and the Battle of Mametz Wood

Perhaps not great but it showed members of operation nightingale digging in Mametz wood.

One figure they quoted was that of 120,000 welshmen who took part in the war, 40,000 were killed which was the highest % of all the allied nations who took part.

BBC Wales are showing a series of great war programs over this month, try I player to find them if your interested and hopefully you can watch them.