Diamond Head: Oahu's Gem
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| Diamond Head View from Waikiki Beach 1 |
Beyond Hawaii's luxury hotels, white sand beaches and stellar golf courses sits Oahu's most prized possession--the Diamond Head State Monument. This 761-foot-tall (23 m) tuff cone looms in the horizon, providing a dramatic backdrop to the island's untamed beauty. The monument is located immediately east of Honolulu, along Diamond Head Road. Surrounded by crystal blue waters and majestic mountains, Diamond Head has become a celebrity in its own right and is an attraction that should not be missed.
HISTORY
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| View of Diamond Head from Above 2 |
Geological History
Diamond Head has a very dynamic geological history, as is apparent by its deeply-eroded
ridges, defined seaward summit and ovoid-shaped crater. Approximately three
million years ago, two shield volcanoes erupted, creating the island of Oahu.
Following the eruptions, the two volcanoes underwent periods of intense erosion,
which left what is known today as the Wai'anae
and Ko'olau
Mountain Ranges. After two million years of dormancy, the southeastern end of
the Ko'olau Mountains suddenly erupted. Because these explosions occurred near
the ocean, the magma was broken down into ash and fine particles which, when
blown into the air, became cemented together into a rock called tuff, forming
the now infamous crater.
Early and Military History
Before this national landmark was named by westerners, it was known to Hawaiians
as Le'ahi. Hawaiian legend claims that Hi'iaka, the sister of fire goddess Pele,
gave the summit this name because of its resemblance to the forehead of the
'ahi fish. The name Diamond Head didn't come into popular usage until the late
1700s when British explorers visited the area and mistook the shining calcite
crystals for diamonds.
Diamond Head has served many purposes throughout the years. In the early history, the summit of this crater was used to light navigational fires that assisted canoes traveling along the shoreline. A temple dedicated to the god of wind was also built on the peak to prevent strong updrafts from putting out the fires. This site soon became an ideal location for the coastal defense of Oahu and in 1904 the area was purchased by the Federal Government, who put it to military use. Diamond Head was fortified four years later with the construction of gun emplacements and an entry tunnel through the north wall of the crater. A total of five batteries were built which housed the coastal artillery. A four-level Fire Control Station was incorporated between 1908 and 1910. This consisted of instrument and plotting rooms that directed artillery fire from several batteries. Additional defense was provided in 1915 when long-range guns were installed on the outer slopes and rim of the crater. Although Diamond Head was prepared to defend Oahu from attacks, no artillery was ever fired during a war.
Today, Le'ahi is one of Hawaii's most recognized landmarks. It was named a National Natural Landmark in 1968 as an excellent example of a tuff cone.
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| Diamond Head State Monument 3 |
ENVIRONMENT AND CLIMATE
Steep, rocky slopes, shallow soil and low shrubs and herbs make up the surroundings at the Diamond Head Crater. Until the early 1900s, rainwater collected on the crater floor, forming a small lake inhabited by native ducks, coots and gallinules. Botanists also believe that the area was once blanketed by a dryland forest, however only a few Hawaiian species remain to this day. Some of the commonly seen plants and animals include the kiawe (a relative of the mesquite), koa haole, doves, sparrows and cardinals.
Oahu's climate can be summarized as pleasantly mild, although there are many variations within short distances on the island due to the various elevations and coast exposures. The northeasterly trade winds, as well as the two mountain ranges are the dominant factors that govern the climate. Both the Wai'anae and Ko'olau Mountain Ranges serve to block the trade wind moisture, which causes Diamond Head's climate to be much drier and hotter than other parts of the island. Temperatures vary annually between 60° F (15° C) and 90° F (32° C). Summer temperatures range from 68° F (20° C) to 90° F (32° C), while the winter temperature is around 60° F (15° C) to 80° F (27° C). There is also more rainfall during the winter, and because of the mountains, most of it falls on the northeastern or Windward side. However, Diamond Head remains dry, dusty and very hot so visitors are advised to bring along sunscreen, a hat and plenty of water during their trip.
ACTIVITIES AND ATTRACTIONS
A Historic Hike
To truly appreciate the Diamond Head cone, one must hike up the crater. An extensive
trail leads up to the top of the Diamond Head summit. Built in 1908 as part
of the U.S. Army Coastal Defense System, the dirt trail was originally designed
for mule and foot traffic. Today, the trail involves a 0.7 mi (1.1 km) hike
and 560-foot (171 m) climb. The trail runs through an uneven and steep terrain
that requires appropriate footwear. To get to the top of the crater, visitors
will have to climb a set of steep stairways and go through a dark tunnel. The
Diamond Head trail takes visitors up the inside slopes of the crater, past and
through some of the military bunkers. Although hand rails are provided, guests
are also advised to have a flashlight ready for the hike to the peak.
The trailhead begins at the parking lot on the crater floor 200 ft (61 m) above sea level. A short concrete walkway follows, which then turns into the 1908 trail alignment, consisting of various switchbacks. A concrete landing and lookout post is situated about halfway up the hike. This point originally held a winch and cable to lift materials from the crater floor to a midway point. A subsequent stairway of 74 steps leads into the first narrow tunnel. This dark 225-foot-long (69 m) passage transcends into a second staircase consisting of 99 steep steps. Next, visitors climb a spiral staircase, exiting through slits at the back of the crater. The trip to the top of Diamond Head ends with a final short series of stairs where guests are greeted with spectacular 360° views of Waikiki, Honolulu, Koko Head and the outlines of the Maui and Moloka'i islands. A round-trip takes anywhere from one to two hours, with the option of picnicking at the top.
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| Diamond Head Lighthouse 4 |
Diamond Head Lighthouse
Rising 147 ft (45 m) above sea level, this lighthouse was originally erected
in 1899 on the extinct side of the volcano. Although the present structure was
rebuilt in 1917, the initial ironwork of the watch room and lantern are still
in use. The guidepost now stands 55 ft (17 m) high and can be seen as far away
as 18 mi (29 km). With an intensity of 60,000 candlepower, the tower shines
a red light to steer oncoming vessels away from the reefs of Waikiki
Beach. The original light keeper quarters are on-site as well, which
now act as the residence of the 14th Coast Guard District Commander. The lighthouse
has a unique history of its own, serving as the 14th Coast Guard District Radio
Station and occupying a seat on the National Register of Historic Places. Although
a trail leads to the lighthouse, it sits on private property and permission
must be obtained to enter the vicinity. The Diamond
Head Lighthouse is one of the best-known beacon lights in the Pacific,
as it stands as a sentinel to Honolulu and the Diamond Head State Monument.
PHOTOS COURTESY OF:
- Diamond Head View from Waikiki Beach; Oahu, HI, USA
- View of Diamond Head from Above; Oahu, HI, USA
- Diamond Head State Monument; Oahu, HI, USA
- Diamond Head Lighthouse; Oahu, HI, USA




