The sober and colossal memorial (1936) stands at the top of Hill 145, the highest point of the 14km-long Vimy ridge. It commemorates the attack led here on 9 April 1917 by four divisions of the Canadian Corps in their bid to take control of this key section of the German defence. On the slope, the network of Canadian and German trenches has been restored, as has a part of the Grange Subway, which was originally 750m in length. The ground is still strewn with potholes and craters created by shells and mines.