Hanauma Bay
Maybe the most famous snorkeling beach in the US. The Hanauma Crater was created about 32,000 years ago during the Honolulu volcanic series, the latest (and perhaps final) round of volcanic activity to occur on Oʻahu.[9] Tens of thousands of years ago, a series of volcanic vents opened along the southeast shoreline of Oʻahu. Unlike the gentle lava flows currently building the island of Hawaiʻi, the late-stage eruptions on Oʻahu were most often short-lived violent explosions. The volcanic vents that formed Hanauma Crater opened on the sea floor. Upwelling magma vaporized the ocean water and steam explosions blew the magma into fine ash. The explosions built cones or rings of ash, which solidified into tuff. The eruptions shattered the sea floor—coral reef and basalt—and scattered pieces that are now embedded in the tuff. Wave erosion eventually cut through the low, southeast wall of the crater, forming the current bay. Due to its popularity, officials in Hawai'i have taken several steps to limit visitors and educate those that do come about conserving the reef and marine life.
Hanauma Bay
Maybe the most famous snorkeling beach in the US. The Hanauma Crater was created about 32,000 years ago during the Honolulu volcanic series, the latest (and perhaps final) round of volcanic activity to occur on Oʻahu.[9] Tens of thousands of years ago, a series of volcanic vents opened along the southeast shoreline of Oʻahu. Unlike the gentle lava flows currently building the island of Hawaiʻi, the late-stage eruptions on Oʻahu were most often short-lived violent explosions. The volcanic vents that formed Hanauma Crater opened on the sea floor. Upwelling magma vaporized the ocean water and steam explosions blew the magma into fine ash. The explosions built cones or rings of ash, which solidified into tuff. The eruptions shattered the sea floor—coral reef and basalt—and scattered pieces that are now embedded in the tuff. Wave erosion eventually cut through the low, southeast wall of the crater, forming the current bay. Due to its popularity, officials in Hawai'i have taken several steps to limit visitors and educate those that do come about conserving the reef and marine life.