The Battle of Chinkiang was fought between British and Chinese forces in Chinkiang (Zhenjiang, in modern transcription), China, on 21 July 1842 during the First Opium War. It was the last major battle of the war. The British capture of this stronghold allowed them to proceed forward to Nanking. Fought near the confluence of the Grand Canal and Yangtze River, the battle effectively blocked operation of the Caoyun system, a transport network vital for the movement of grain throughout the empire.