On the Big Island, where nature seems more primordial than anywhere else in Hawai'i, powerful geologic forces etched a date in history even as they swept scores of Hilo residents to watery deaths on the morning of April 1, 1946.
Just before 7 a.m., a powerful tsunami, moving at nearly 490 mph, slammed into the bayfront community. It already had traveled south along the Hawaiian Islands, killing people everywhere in its path.
More than 159 people died, but most — 96 — were killed in Hilo. Many lived in the densely populated Shinmachi neighborhood on what is now Wailoa State Park. Damage was estimated at $27 million.
Eight waves hit Hilo, although only three of them swept through the town with the force of a fire hose. The last one crested at 50 feet and washed half a mile inland.
The power of the waves was enormous. At the Wailuku River, a railroad-bridge span weighing 100 tons was ripped from its pillars and sent upstream.
Entire buildings were leveled, and houses were moved off their foundations. In Hilo Bay, almost 6,000 feet of the breakwater was destroyed. Waves pushed eight-ton blocks of stone all the way to shore.
The bayfront business district was nearly demolished. The railroad was wrecked and the train station gone. A boxcar was shoved through a building, and a boat washed inland 400 feet until came to rest on railroad tracks beside fuel-storage tanks.
The tsunami was triggered by a 7.8-magnitude earthquake below the Pacific on the north slope of the Aleutian Trench, south of Alaska's Unimak Island.
It traveled the 2,240 miles to Hawai'i in slightly more than 4ý hours, with the first wave reaching Kaua'i at about 5:55 a.m. and Hilo at 6:54 a.m.
Between each subsequent wave, the receding waters exposed as much as 500 feet of ocean floor, a sight that drew curious children right into the path of the next incoming wave. Because it had been decades since the last tsunami, many Hilo residents were unaware of the approaching danger.
Children ran to the seawall to explore the naked ocean floor while other residents walked toward the bay to watch what they thought was simply high surf.
The waves carried them all away.
Surges as tall as two- and three-story buildings pounded several coastal villages on the Big Island. To the north, on the low-lying Laupahoehoe Peninsula, 16 schoolchildren and five teachers died.
Many photographs of the tsunamis that struck Hilo, shot during each wave's arrival and after, documented what happened. One of the most famous focused on dock foreman Antone "Tony" Correa Aguiar, his arms folded across his chest as he stared at a mountain of water and debris seconds before he was engulfed.
The photo was taken from the deck of the Brigham Victory, an ammunition-laden ship that was tethered to the pier until Aguiar cut it free, just in time to save it from a tsunami.
Aguiar's body was found later that day at Reed's Bay.
