The Battle of the Somme was fought between July and November 1916, and is often called one of the defining events of the First World War.
It was the largest battle on the Western front and saw over one million wounded, killed or missing in action on both sides.
July 1 1916, was - and still is - the deadliest day in the history of the British Army. Almost 20,000 British Empire soldiers lost their lives in just 24 hours.
As well as being the deadliest battle of the 1914-1918 conflict, it was also one of the bloodiest battles in human history.
There are a number of different events happening across our region to commemorate the Battle of the Somme.
Here's what's going on in your area:
- BRISTOL - (OVERNIGHT)
Clifton Cathedral will be holding an all-night vigil - starting at 8.30pm with an interfaith service involving representatives from the City's main religious communities.
There will be prayers and reflections throughout the night and at 7.30am on July 1 - exactly one hundred years after the start of the Battle - Reveille will be followed by Mass.
- GLOUCESTER CATHEDRAL - (0715)
A Tommy helmet and an Officer's Cap from the First World War will be placed centrally either side of a single candle on the altar and the citation of the holder of the Victoria Cross will be read aloud.
At 7.30am 'Whistle for the Somme' will be observed at the War Memorial on Lower College Green. The Dean will blow a whistle to mark the moment that the troops went 'over the top'.
- SALISBURY TRENCH EXPERIENCE - (0715-1700)
A scale section of a First World War trench is on display at Chalke Valley History Festival.
It's built by a team of experts and local volunteers, using authentic methods and materials, official period manuals, as well as drawing upon the testimonies of those who built and fought in them.
It's thought this will be as close a representation of what a First World War trench was like as is possible.
- STROUD - (1000-1300)
A memorial exhibition is being presented by the Five Valleys Great War Researchers at Stroud Congregational Chapel.
It will tell the story of local men who fought at the Battle of the Somme.
- SWINDON CENOTAPH - (1045)
A two minutes silence and service will be held at the Cenotaph at Swindon city centre. Followed by a drop in at the Royal British Legion.
- BURNHAM ON SEA - (1100)
St. Andrew's Church will be holding a commemoration service beginning at 11. It includes a roll-call of local people who died at the battle.
- FRESHFORD VILLAGE CENOTAPH - (1100)
The village will remember Ernest Rouse, a Freshford Villager who died on that day.
- SHEPTON MALLET CENOTAPH - (1200)
A Service of Commemoration will be help where standard-bearers of the Light Infantry Association from Bath, Bristol, Taunton and Midsomer Norton will be present, in addition to the Shepton Mallet Royal British Legion branch Standard.
Students from Whitstone School will read the names of the 17 men from Shepton Mallet listed on the Cenotaph who were killed in the various battles of The Somme.
- YEOVIL LIBRARY FILM - (1430)
There will be a free screening of 1916 documentary 'The Battle of the Somme' - the first feature length documentary about war and changed the way both cinema and film was perceived by the public.
In the year of its release, around 20 million people - almost half the population - watched the film, many hoping to see the image of a loved one or friend.
- CHELTENHAM - (1530)
There will be a parade and service outside the Pittville Pump Rooms.
A parade of flags and local youth cadets including motorbike riders who will lead the parade. There will also be a bag piper and a drummer with a dozen standards.
The parade is followed by hymns, prayers, and poetry readings and a roll call of the dead from the local area who have no known grave.