Urakami is the northern district where the atomic bomb detonated on 9 August 1945. Before the war it was the centre of Japanese Catholicism — for two and a half centuries Urakami's hidden Christians had practised their faith in secret, and when the prohibition was lifted in the 1870s they built the largest cathedral in East Asia here. The bomb destroyed almost everything within a kilometre radius. The valley today is a quiet residential area structured around the Peace Park, the Atomic Bomb Museum, the rebuilt cathedral, and the Hypocenter Park — all within easy walking distance of each other. The Matsuyama-machi tram stop is the closest to the core memorial sites.