IN FIGURES

● 325,000 Estimated Allied casualties, including many Australian, New Zealand and Canadian soldiers. The Germans lost between 260,000 and 400,000.

● 4.25 million Shells fired at the German lines from 3,000 big guns in the two weeks before the battle started – alerting them to an imminent attack.

● 103 Days that the battle lasted, between 31 July and 10 November, 1917.

● 30 The weather in Flanders during the offensive was the worst in the region for 30 years, reducing much of it to a quagmire.

● 127mm Amount of rain (five

inches) that fell on Passchendaele in August 1917. The average for the UK in August 2016, by comparison, was 85.5mm (3.4 inches).

● 1.7: Distance in miles the British advanced between 31 July and 2 August, 1917 – the equivalent of Downing Street to St Paul’s Cathedral in central London.

● 32,000: Casualties they suffered during that period.

● 1,200: British casualties per 100 metres gained in those first opening three-day campaign of fighting.

Sources PA Archive, Met Office, War Office Archive, Ministry of Defence, Imperial War Museum