The Battle of Iwo Jima took place on the island of Iwo Jima, located 750 miles south of Tokyo, Japan. The Japanese had fortified the island with over 1,500 interconnected underground tunnels and bunkers. Their strategy was to inflict heavy casualties on the invading American forces without surviving themselves. Over 21,000 Japanese defenders awaited the arrival of 110,000 US Marines in February 1945. The battle resulted in nearly 7,000 US casualties and over 20,000 Japanese deaths as they fought ferociously from their fortified underground positions. Although a key victory for the US, it came at a heavy cost in military lives.