Diamond Head State Monument

The name

Sailors named it Diamond Hill in 1825, after crystals they took for diamonds

Known to Hawaiians as Lēʻahi, most likely because the ridgeline resembles a tuna's dorsal fin. In 1825 British sailors discovered sparkling volcanic calcite crystals in the sand and mistook them for diamonds. The name later became Diamond Head.

The cone

Diamond Head is a tuff cone about 400,000 to 500,000 years old

Diamond Head is a volcanic tuff cone on Oʻahu, part of the Honolulu Volcanic Series formed by renewed eruptions from the Koʻolau Volcano. The Koʻolau Range is about 2.6 million years old, and Diamond Head is much younger.

2.6 millionyears, the age of the Koʻolau Range, far older than the cone

The trail

The trail to the summit was built in 1908 for the Army's coastal defense

The crater was home to Fort Ruger, the first United States military reservation in Hawaii. The trail was originally built in 1908 as part of the U.S. Army Coastal Defense System. It rises 560 feet, and bunkers at the summit directed artillery fire.

560 feetthe rise of the trail to the summit

Festivals

Hawaiian Woodstock held music festivals in the crater from 1969

The Diamond Head Crater Festivals were all-day music celebrations of the 1960s and 1970s, first held on New Year's Day 1969 and often known as Hawaiian Woodstock. They drew over 75,000 attendees, and were canceled over community noise and environmental impact concerns.