Mount Isarog
Stratovolcano located in the province of Camarines Sur, Philippines
Isarog is an active stratovolcano located in the province of Camarines Sur, Philippines, on the island of Luzon. The mountain has active fumaroles and hot springs. It has an elevation of 2,000 m (6,600 ft) above mean sea level.
The broad isthmus between Lagonoy Gulf and San Miguel Bay is occupied by the isolated Isarog volcano.
The volcano has a 2,500 m-wide (8202 ft) crater that is breached to the east along a narrow valley drained by the Rangas River. A major debris avalanche deposit extends northwest to the coast and into San Miguel Bay.
The peak of the mountain marks the point where the borders of six municipalities and one city meet (listed in clockwise direction, starting north): Goa, Tigaon, Ocampo, Pili, Naga City, Tinambac and Calabanga.
Isarog Volcano was where local troops of the Philippine Army and Constabulary units and Bicolano guerrillas hid during the Japanese Occupation. In the 1970s, with the leadership of Romulo Jallores and his brother, they established the New People's Army in the Bicol region at the foot of this mountain.
Geology
Isarog Volcano is interpreted to have formed during the Pleistocene, as indicated by K-Ar dating of lava samples from the edifice, which yielded an age of 0.16 ± 0.12 Ma.
The public source identifies “Mount Isarog” as stratovolcano located in the province of Camarines Sur, Philippines. This brief keeps that definition visible, then builds a research path around Mount, Isarog and Stratovolcano.
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The strongest evidence will usually combine a dated visual record with documents produced by the authority responsible for the place. The source revision retrieved here is dated Aug 15, 2026. The linked authority identifier is Q1673747. Authority coordinates are 13.659, 123.373. 1 of 1 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank.
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This entry incorporates text from “Mount Isarog” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.