Dozens of aging U.S. veterans gathered on the tiny, barren island of Iwo Jima on Saturday to mark one of the bloodiest and most iconic battles of World War II 70 years ago.

The vets, many in the early 90s and some in wheelchairs, toured the black sand beaches where they invaded the deeply dug-in forces of the island's Japanese defenders.

They were bused to the top of Mount Suribachi, an active volcano, where an Associated Press photo of the raising of the U.S. flag while the battle was still raging became a potent symbol of hope and valor to the war-weary public back home that was growing increasingly disillusioned with the seemingly unending battle in the Pacific.

For some of the veterans, the return to the island where many of their comrades died and which is still inhabited only by a contingent of Japanese military troops, brought out difficult emotions.

"I hated them," said former Sgt. John Roy Coltrane, 93, of Siler City, North Carolina. "For 40 years, I wouldn't even buy anything made in Japan. But now I drive a Honda."

Speeches at the Reunion of Honor ceremony held near the invasion beach were made by senior Japanese politicians, descendants of the few Japanese who survived the battle. Also speaking were the U.S. secretary of the Navy and the commandant of the Marine Corps, who noted that the battle for Iwo Jima remains at the "very ethos" of the Marine Corps today.

The Marines invaded Iwo Jima in February 1945, and it was only declared secured after more than a month of fighting. About 70,000 U.S. troops fought more than 20,000 Japanese — only 216 Japanese were captured as POWs and the rest are believed to have been either killed in action or to have taken their own lives.

The island was declared secure on March 16, 1945, but skirmishes continued. In about 36 days of battle, nearly 7,000 U.S. Marines were killed and 20,000 wounded.

Though a tiny volcanic crag, the island — now called Ioto on Japanese maps — was deemed strategically important because it was being used by the Japanese to launch air attacks on American bombers. After its capture, it was used by U.S. as an emergency landing site for B-29s, which eventually made 2,900 emergency landings there that are estimated to have saved the lives of 24,000 airmen who would have otherwise had to crash at sea.

All told, 27 Medals of Honor were awarded for action in the battle, more than any other in U.S. military history.