Households and buildings across the country are being asked to switch off at 10pm as part of Lights Out, a nationwide event which is inspired by a quote from Sir Edward Grey, who was Foreign Secretary in 1914.  On the 3 August 1914, the evening before the outbreak of war, he said: “The lamps are going out all over Europe; we shall not see them lit again in our lifetime.”

Britain declared war at 11pm on 4 August 1914.

Lights Out encourages people to turn off all lights except one at 10pm, leaving that single light as a symbol of hope and reflection.

The Wills Memorial Building has frequently been illuminated in different colours to raise awareness of specific causes, but it is very rare for the external lights to be extinguished altogether.

The distinctive external lighting was switched on in 2008 by World War 1 veteran Harry Patch to celebrate completion of the tower refurbishment project.

Harry had worked on the construction of the Wills Memorial Building as a plumber for three years and attended the formal opening of the building on 9 June 1925 by King George V and Queen Mary.

He was the last surviving British soldier to have fought in the trenches of the Western front, and was injured in 1917 at Passchendaele, the Third Battle of Ypres.

Lights Out is organised by 14 - 18 NOW WW1 Centenary Art Commissions which is a major cultural programme taking part across the country this summer to mark the start of World War 1.