Tantalus is an extinct cinder cone

Cinder cone

According to the , Cinder Cone is the proper name of 1 cinder cone in Canada and 7 cinder cones in the United States:In Canada: Cinder Cone In the United States:...

 in the southern Koolau Range

Koolau Range

Koolau Range is a name given to the fragmented remnant of the eastern or windward shield volcano of the Hawaiian island of Oahu. It is not a mountain range in the normal sense, because it was formed as a single mountain called Koolau Volcano...

 on the Hawaiian Island

Hawaiian Islands

The Hawaiian Islands are an archipelago of eight major islands, several atolls, numerous smaller islets, and undersea seamounts in the North Pacific Ocean, extending some 1,500 miles from the island of Hawaii in the south to northernmost Kure Atoll...

 of Oahu

Oahu

Oahu or Oahu , known as "The Gathering Place", is the third largest of the Hawaiian Islands and most populous of the islands in the U.S. state of Hawaii. The state capital Honolulu is located on the southeast coast...

. It also has a summit crater, Tantalus Crater. The cinder cone formed after the demise of Koolau Volcano, during a time of rejuvenated stage volcanism in southeastern Oahu that also formed Punchbowl Crater

Punchbowl Crater

Punchbowl Crater is an extinct volcanic tuff cone located in Honolulu, Hawaii. It is the location of the National Memorial Cemetery of the Pacific....

, Diamond Head

Diamond Head, Hawaii

Diamond Head is the name of a volcanic tuff cone on the Hawaiian island of Oahu and known to Hawaiians as Lēahi, most likely from lae 'browridge, promontory' plus ahi 'tuna' because the shape of the ridgeline resembles the shape of a tuna's dorsal fin...

 and Koko Head

Koko Head

Koko Head is the headland that defines the eastern side of Maunalua Bay along the southeastern side of the Island of Oahu in Hawaii. On its western slope is the community of Portlock, a part of Hawaii Kai...

. Tantalus overlooks the modern city of Honolulu, which is built on top of Tantalus cinders.

The southern slope of Tantalus was bombed in Operation K

Operation K

was a Japanese naval operation in World War II, intended as a reconnaissance of Pearl Harbor and disruption of repair and salvage operations following the surprise attack on December 7, 1941. It culminated on March 4, 1942, with an unsuccessful attack carried out by two Kawanishi H8K "Emily" flying...

, Japan's unsuccessful second attack on O'ahu, which took place March 4, 1942.

Today, Tantalus is a popular hiking

Hiking

Hiking is an outdoor activity which consists of walking in natural environments, often in mountainous or other scenic terrain. People often hike on hiking trails. It is such a popular activity that there are numerous hiking organizations worldwide. The health benefits of different types of hiking...

destination.