Rare charts show WW1 German air raids on Britain A secret First World War map showing the routes of German bombing planes over London, Kent and the Thames Estuary He added: "The bombing war has fallen off people's radars, but right through the First World War there was strategic bombing." One of the most unusual documents in the new collection was the chart drawn up by the British authorities, after a German bombing raid on London and the south east on the evening of December 6, 1917. Click here to see a high resolution version of the map showing routes of German bombing planes over London The chart was intended to help to improve air defences by indicating the routes the German raiders used. Officials used reports from spotters on the ground, as well as British fighter aircraft which had been scrambled to intercept the invaders. The resulting chart shows the 16 Gotha bombers, flying in four detachments, entering British airspace over a wide area of Kent and Essex. Some bombs are dropped on coastal targets in Kent, but most are reserved for the capital - each bomb being marked by a red dot on the map. During the raid fire engines had to be called from as far afield as Wembley and Twickenham to attend a fire in Shoreditch. The aerial photographs of targets in London were taken later in the war, on May 21 1918, by a German aircraft. They show ships in the Victoria and Albert Docks, and the George V Dock under construction. The surrounding area also contained many factories, warehouses and works that the Germans targeted. The Royal Arsenal was at Woolwich, on the south bank. One other document in the collection - which was widely circulated at the time - is a map drawn up by a newspaper in 1919, showing the position of every aircraft or Zeppelin bomb dropped on London during the war. They show a trail of explosives dropped along the A23 in south London, as well as other clusters in the City and Bethnal Green and Stoke Newington areas. Although more commonly associated with the Second World War, such strategic bombing campaigns were also a feature throughout the Great War. The first Zeppelin raid on Britain took place on the evening of January 19 1915 when two airship bombed Great Yarmouth and King's Lynn in Norfolk, killing nine people. More raids followed on coastal towns and also on London during 1915 and 1916. In all, there were fifty two Zeppelin raids on Britain during the war, killing over 500 people. Large scale raids by Gotha IV bombers began on May 25 1917, with a second attack on 5 June. The first daylight raid on London, on June 13, killed 162 people, including 18 children in a primary school in Poplar, and injured 432. In this, the deadliest raid of the war, no Gothas were shot down. Between May and August 1917, eight daylight raids were carried out over England, including three on London. Beginning in September, improved British air defences forced the Germans to abandon daylight raids and switch to night operations, but heavy losses forced these to be suspended in February 1918. On the night of 19 May 1918, 38 Gothas made the last and largest raid of the war on London, losing six planes to fighters and anti-aircraft fire with a seventh crashing on landing. In all, Gothas carried out 22 raids on England, dropping 186,830lb of bombs for the loss of 61 aircraft. As well as the images relating to the bombing campaign, the new book also contains around 150 other maps from the Imperial War Museum archives, most of which have not been published since the end of the war. They range from small-scale charts showing country boundaries and occupied territories to large-scale maps of key battles and offensives, trench maps depicting detailed front line positions and naval charts. Millions of military and commercial maps were printed during the war, many of which reflect major developments in artillery and aerial reconnaissance.