80 ton Cannon - these were made at Woolwich. From before 1700 the Royal Arsenal in Woolwich was a extensive government factory for arms manufacture, research and testing. At its peak in the First World War it covered 1,285 acres and employed close to 80,000 people. Later in the C20th the operations were scaled down; it finally closed as a factory in 1967. Along the river on what is now Greenwich Peninsula the Blakely Ordnance Company also manufactured cannons.