They called it The Big Push.
The Somme in 1916 was designed to be a decisive breakthrough in the First World War but was instead a costly failure.
On Friday July 1 we mark 100 years since the start of the battle. It began after a series of mines were detonated, the signal for soldiers to go over the top.
One of the explosions left a huge crater which a century on has become the focus of remembrance and reflection.
We speak to: Lochnagar Crater owner Richard Dunning and historian Alex Churchill, author of Somme: 141 Days, 141 Lives. Also to Michael Fellows and Richard Frankish, whose fathers fought on The Somme.
Preparations are underway to mark 100 years since The Somme - one of the deadliest battles in British history.
Relatives, politicians and members of the Royal Family will attend a series of commemorative events in France next week remembering the more than one million men on both sides who were killed or wounded.
The battle, which began on on July 1 1916, was an attempt to break the deadlock during the First World War when soldiers were dug into miles of trenches and ditches.
We speak to: Betty Foster, who was visiting her uncle's grave on The Somme; Alex Churchill, author of 'Somme: 141 days, 141 lives' - and Phil Betts of the Frittenden Historical Society.
A special service has been held in Southampton to commemorate the lives of more than 600 African servicemen who died off the coast of the Isle of Wight during World War One.
The tragedy was South Africa's worst wartime naval disaster, and it happened exactly 99 years ago this weekend. The ship sank in thick fog, as Richard Slee reports.
The interviewees are Lt Col Rui Goncalves, Angolan Defence Attache; and Obed Mlaba, the South African High Commissioner.
For many people, the opening of the arch, which has already become a landmark on the clifftop, is the result of a very long campaign. David Johns reports, talking to Parade Commander Alan Warren and veteran Raymond Whitewood.
Pictures just in from Folkestone, where Prince Harry is dedicating the new memorial arch in the town.