Huilua Fishpond , in Ahupuaa O Kahana State Park on windward Oʻahu , is one of the few surviving ancient Hawaiian fishponds that were still operational well into the 20th century . It was declared a U.S. National Historic Landmark in 1962 , shortly after it had been severely damaged by the 1960 tsunami . It was added to the National Register of Historic Places on L : December 29 , 1962
1960 tsunami
1960 Valdivia earthquake
Huilua Fishpond