Westerplatte is a peninsula in the Gdansk harbour channel and a cherished symbol of the Polish resistance at the outbreak of WWII. It is famed for the Battle of Westerplatte, the first major battle after the German invasion of Poland in 1939. From 1926-1939 there was a Polish military outpost, equipped with one 75mm field gun, two 37mm antitank guns (slightly mystifying for a coastal defense), four mortars and several medium machine guns. There were no real fortifications, only several concrete barracks and blockhouses. The garrison was attacked by German naval infantry on 1 September 1939. The heavy attacks were repelled by the Poles for seven days, until they were forced to surrender on 7 September. The ruins of the barracks are still to be found at Westerplatte. One of them was transformed into a museum commemorating the battle. At the entrance are two shells from the German warship Schleswig-Holstein. There is also a tall stone monument and memorials to fallen soldiers.