USGS Hawaiian Volcano Observatory scientists monitor Mauna Loa, the largest active volcano on Earth. In this 1985 aerial photo, Mauna Loa looms above Kīlauea Volcano’s summit caldera (left center) and nearly obscures Hualālai in the far distance (upper right).
Where is the largest active volcano in the world?
Rising gradually to more than 4 km (2.5 mi) above sea level, Hawaii’s Mauna Loa is the largest active volcano on our planet. Its submarine flanks descend to the sea floor an additional 5 km (3 mi), and the sea floor in turn is depressed by Mauna Loa's great mass another 8 km (5 mi). This makes the volcano's summit about 17 km (10.5 mi) above its base!
Learn more: USGS Hawaiian Volcano Observatory
Related
What was the largest volcanic eruption in the 20th century?
Which volcanic eruptions were the deadliest?
Where does the United States rank in the number of volcanoes?
What was the most destructive volcanic eruption in the history of the United States?
What are some examples of supervolcanoes?
What are some benefits of volcanic eruptions?
How big are the Hawaiian volcanoes?
How hot is a Hawaiian volcano?
USGS Hawaiian Volcano Observatory scientists monitor Mauna Loa, the largest active volcano on Earth. In this 1985 aerial photo, Mauna Loa looms above Kīlauea Volcano’s summit caldera (left center) and nearly obscures Hualālai in the far distance (upper right).
Erupting vents on Mauna Loa’s northeast rift zone near Pu‘u‘ula‘ula (Red Hill) on Mar. 25, 1984, sent massive ‘a‘ā lava flows down the rift toward Kūlani.
Erupting vents on Mauna Loa’s northeast rift zone near Pu‘u‘ula‘ula (Red Hill) on Mar. 25, 1984, sent massive ‘a‘ā lava flows down the rift toward Kūlani.

Part 1 of 5

Part 2 of 5

Part 3 of 5

Part 4 of 5

Part 5 of 5
The lava flow that came to Hilo—The 1880–81 eruption of Mauna Loa volcano, Island of Hawai‘i
Living with volcano hazards
2018 update to the U.S. Geological Survey national volcanic threat assessment
Characteristics of Hawaiian volcanoes
Mauna Loa--history, hazards and risk of living with the world's largest volcano
Eruptions of Hawaiian volcanoes—Past, present, and future
Related
What was the largest volcanic eruption in the 20th century?
Which volcanic eruptions were the deadliest?
Where does the United States rank in the number of volcanoes?
What was the most destructive volcanic eruption in the history of the United States?
What are some examples of supervolcanoes?
What are some benefits of volcanic eruptions?
How big are the Hawaiian volcanoes?
How hot is a Hawaiian volcano?
USGS Hawaiian Volcano Observatory scientists monitor Mauna Loa, the largest active volcano on Earth. In this 1985 aerial photo, Mauna Loa looms above Kīlauea Volcano’s summit caldera (left center) and nearly obscures Hualālai in the far distance (upper right).
USGS Hawaiian Volcano Observatory scientists monitor Mauna Loa, the largest active volcano on Earth. In this 1985 aerial photo, Mauna Loa looms above Kīlauea Volcano’s summit caldera (left center) and nearly obscures Hualālai in the far distance (upper right).
Erupting vents on Mauna Loa’s northeast rift zone near Pu‘u‘ula‘ula (Red Hill) on Mar. 25, 1984, sent massive ‘a‘ā lava flows down the rift toward Kūlani.
Erupting vents on Mauna Loa’s northeast rift zone near Pu‘u‘ula‘ula (Red Hill) on Mar. 25, 1984, sent massive ‘a‘ā lava flows down the rift toward Kūlani.

Part 1 of 5

Part 2 of 5

Part 3 of 5

Part 4 of 5

Part 5 of 5