Thought I would share this link I found on the news this morning , as I do find both world wars extremely interesting and it?s actually a good write up for the news .

https://www.google.co.uk/amp/s/www.bbc.com/news/amp/world-europe-56370510

Hope somebody else enjoys the read 

There was a report on it this morning on BBC Radio 4 Today.

That failed offensive - some say the French version of the Somme battle(s) - led to the dismissal of Nivelle and mutinies in the French army. It was a Franco-British affair with the British attacking at Arras to draw forces away from the Chemin des Dames area. The British continued to attack for the rest of the year culminating in the battle of Passchendaele  3rd Ypres).  Humungous loss of life on both sides.

Yes I have read about those battles very sad news I don?t no much about the french side of the story other than we had to draw the Germans attention so they didn?t get over run completely.

The battle of the Somme in 1916 was originally planned as a joint Franco-British knockout blow. Pressure on the French at the battle/siege of Verdun meant the British & Commonwealth forces had to do much of the fighting. Failures of command, tactics, planning, artillery and the compactness of the battlefield led to the horrific slaughter of the volunteers, notably the "pals" battalions.

I really enjoy the two episodes of this documentary I think it?s very good have you watched this 1?

https://m.youtube.com/watch?v=S88vie0eCnA

You may find the activities of the tunnelling battalions interesting - they were almost all ex-miners. One of the main reasons the German defence on the Somme was successful was the deep dugouts they constructed in the chalk.

The Allies were also handicapped in Flanders by the Germans occupying the higher ground. To counterract this the British dug mines underneath the German positions and filled them with ammonal. Detonating these was the key to some less costly Allied victories in the second half of the war. Research the battles of Vimy & Messines Ridges.

Turin was defended by digging tunnels underneath the attacking army and then blowing them up. This was about 1706 during the middle of the Spanish War of succession.
The museum over the tunnels is called The Pietro Micca civic museum. Pietro blew up the tunnels and himself when the invading forces had discovered the way in underneath the citadel. The citadel was not captured.

https://www.youtube.com/watch?v=MtsEBv0x_nM

It's been known since at least the times of the Greeks & Romans: https://en.m.wikipedia.org/wiki/Tunnel_warfare

& Italian defences in WW1 also used via ferrata.