Kahaluu Fishpond - Credit: Wikimedia Commons
Kahaluu Fishpond, historically known as Kahouna Fishpond, on Kāneohe Bay in windward Oʻahu, is one of only four surviving ancient Hawaiian fishponds on Oahu that were still in use well into the 20th century. In the previous century there were at least 100 such fishponds around the island. Kahouna was in use until about 1960 and was added to the National Register of Historic Places in 1973, after members of the surrounding community raised concerns that it would be destroyed by development. The Kahaluu Taro Lo'i Historic District was also added to the National Register at that time. Read more on Wikipedia
Source: en.wikipedia.org