From nearly any vantage point on Kamchatka, mountains and volcanoes define skylines. The peninsula's 29 active volcanoes comprise 10% of the world's volcanic activity.

     Volcanologists and historians tell us that Avachinsky Volcano, which overlooks Petropavlovsk, has erupted at least 16 times since 1737. In 1787, the French explorer Jean-Francios de Galaup La Perouse became the first person to climb Avachinsky Volcano. The most recent eruption in 1991 produced lava flows, a dome, and mudflows. Avachinsky constantly steams and those willing to hike to the summit can peer down into the gaseous crater.  Neighboring Koryaksky most recently erupted in 1956, exploding at the summit and upper northwest side of the volcano. On the eastern flank of Avachinsky Volcano is the extinct Kozelsky Volcano (2189 m) and on the northwest border of Koryaksky Volcano slumbers extinct Aag Volcano (2330 m). Across Avacha Bay to the south the symmetrical Vilyuchinsky Volcano gives the Petropavlovsk and Yelizovo area a panorama of active and extinct volcanoes.

     This volcanic abundance results from the subduction beneath the Okhotsk Plate by the Pacific Plate creating seismic and volcanic activity from Honshu and Hokkaido, Japan up the Kuril Islands and the length of the Kamchatka Peninsula. The Kuril-Kamchatka subduction zone contains 150 volcanoes that have erupted over the last 10,000 years. According to the Smithsonian Institution's Global Volcanism Program, about 2-dozen volcanoes have been very active in the Kurils and Kamchatka area since 1960.

     None of the volcanoes of Kamchatka’s Sredinny Range have erupted in historic times. Kamchatka's hot spots are located along the Vostochniy Kamchatka Range and since 1960, 4 volcanoes have accounted for the most frequent eruptions. These include giant Klyuchevskoy, Eurasia's highest active volcano (4750 m), Bezymyanny (2882 m), Shiveluech-Kamchatka's largest volcano by volume, and Karymsky Volcano.  Karymsky Volcano has erupted about 30 times since its first historic eruption in 1771. Karymsky's latest activity occurred in 1976.

     Klyuchevskoy Volcano is the most active and powerful of the Kuril-Kamchatka area and the highest active volcano in Eurasia. This massive volcano is part of the Klyuchevskaya group of volcanoes on the right bank of the Kamchatka River in north central Kamchatka.  Klyuchevskoy has an average outflow of lava that accounts for I for the entire Kuril-Kamchatka belt of volcanoes. S. P. Krasheninnikov in 1737 was the first to write about witnessing an eruption of Klyuchevskoy.

     In 1975-76, Tolbachik Volcano (3085 m) was the site of Kamchatka's largest basaltic eruption in historic time. This eruption resulted in the formation of four new cinder cones, an eruption cloud reaching 8 miles (13 km) in height, and 260-foot-thick lava sheets covering a 15+ square mile area (40 square km).

     South of Petropavlovsk-Kamchatsky and Yelizovo is the massive Mutnovsky Volcano (2322 m). Mutnovsky, last erupting in 2000, has large twin craters with lakes in them. The very active fumeroles or gas/steam vents, along with pumice beds, cones, and lava flows create a surreal atmosphere.

     Gorely Volcano is 75 km south of Petropavlovsk-Kamchatsky, near Mutnovsky Volcano. The present volcano has 11 superimposed craters at the summit dating back between 6,000 and 8,000 years ago when the volcano was formed by many eruptions.  Inside the craters of Gorely are acid blue lakes. Experiencing the volcanoes of Kamchatka is like watching the Earth in the making. Seeing this dynamic process itself is worth a trip to Kamchatka.