Dick Quinn has lived at the foot of Diamond Head since 1980, but until five years ago he didn’t know much about it.

The retired medical malpractice and hospital law attorney had often walked and jogged around Diamond Head, but except for a rock concert in 1970, he had never been in the crater. In fact, he never considered hiking the Diamond Head Summit Trail until a friend described the spectacular view at the top.

"I wanted to see what was up there myself," Quinn said. "I did the trail for the first time in May 2006, and my first impression was, ‘Wow, awesome, breathtaking, thrilling!’ The scenery stretches from the Waianae mountains all the way to Koko Head. On clear days you can even see Maui, Molokai and Lanai. In January I saw three pods of whales, including one breaching baby and several dolphins from atop Diamond Head."

Hawaii’s most famous landmark was formed more than 150,000 years ago, when lava flowed into the ocean off the southern coast of Oahu. Massive steam explosions propelled ash and pulverized rocks high into the air. When the material fell back to earth, it created the 760-foot tuff cone and its 350-acre crater.

Hawaiians dubbed the distinctive formation Laeahi, meaning "brow of the ahi," because it resembled the head of the yellowfin tuna. "Laeahi" also means "wreath of fire" in reference to fires that were lit on the summit to guide canoes. Navigators erected a heiau there and dedicated it to Laamaomao, the wind goddess, so she would not extinguish their lofty beacons.

In the late 1700s, calcite crystals sparkling on Laeahi’s slopes caught the eye of Western explorers and traders, who mistook them for diamonds. That inspired the name Diamond Head that has endured to this day.

Encompassing more than 475 acres, including the crater’s exterior slopes, Diamond Head State Monument was established in 1965. Three years later the prominent tuff cone was designated a National Natural Landmark.

The federal government bought Diamond Head in 1904 because its panoramic view made it an ideal location for the Army’s coastal artillery defense system. Built in 1908, the steep, rocky summit trail is eight-tenths of a mile long and ascends 560 feet from the crater floor via numerous switchbacks.

Between 1908 and 1910, mules hauled materials up the trail to construct the four-level Fire Control Station, which housed instruments and plotting rooms to direct artillery fire from Batteries Randolph and Dudley at Fort DeRussy in Waikiki and Batteries Harlow (constructed in 1910) and Birkhimer (1916) at Diamond Head.

Hikers are able to spot Birkhimer and three other batteries from the trail: Dodge and Hulings (built in 1913) and Battery 407 (which dates back to 1943). Harlow can be seen outside the crater, across the chapel on the campus of Kapiolani Community College. All five batteries are part of the Fort Ruger Historic District, which was placed on the National Register of Historic Places in 1984.

In addition to a glorious view, the trail offers a great workout. To reach the summit, you’ll have to climb four sets of steps (279 in all). More than 800,000 visitors went to Diamond Head last year; between 2,000 and 2,500 people hike the trail every day.

It’s a part of Quinn’s regular exercise routine. Every other day, he walks from his apartment into the crater, up and down the trail, and around Diamond Head back home.

"It takes me between 2 1/4 and 2 1/2 hours to complete that 7.5-mile route," Quinn said. "Although I’ve seen the view from the summit hundreds of times, it still amazes me: ‘Wow, awesome, breathtaking, thrilling!’ When the light and air quality are good, the mountains are like carved emeralds, and the ocean sparkles like diamonds. Add leaping whales and dolphins, and the experience is pure joy and exhilaration."

State buffs up Diamond Head summit trail

The Department of Land and Natural Resources’ Division of State Parks has started work on the last phase of enhancements to the Diamond Head summit trail.

During Phase 1 and Phase 2 of the three-year, $3 million project, drainage was improved, loose rocks were removed or anchored on the crater’s slopes, sections of the path were resurfaced and repairs were made to areas that had deteriorated due to erosion and heavy visitor traffic.

Phase 3 includes repairing a lookout and a ledge near the summit and constructing a new section of the trail, which will run below the rim with a view toward Koko Head. Partial trail closures might be required when work on the ledge begins (time to be announced). Phase 3 should be finished by July.

A separate project, set to begin in the next two months and completed by fall, is a new path that will run along Diamond Head’s exterior slopes, between 22nd Avenue and the site of the former Cannon Club near Diamond Head Road and Trousseau Street.

Cheryl Chee Tsutsumi is a Honolulu-based freelance writer whose travel features for the Star-Advertiser have won multiple Society of American Travel Writers awards.