363 articles
San Gorgonio Mountain
San Gorgonio Mountain (Old Grayback), 11,503 ft, is the highest peak in Southern California and the Transverse Ranges, in the 37,980-acre San Gorgonio Wilderness of the San Bernardino Mountains.
San Jacinto Peak
San Jacinto Peak, 10,834 ft, highest summit of the San Jacinto Mountains, California; ultra-prominent peak (8,299 ft prominence, No. 6 in contiguous US) in Mount San Jacinto State Park, reached via the Palm Springs Aerial Tramway.
San Pedro-Pellado
San Pedro-Pellado (also San Pedro-Tatara) is a Chilean volcanic complex in the Southern Andean Volcanic Arc, built inside the 6 x 12 km Río Colorado caldera; Pellado, Tatara, and 3,621-m San Pedro stratovolcano, no historical eruptions, fumaroles SE of Pellado.
San Vicente
San Vicente (Chichontepec) is El Salvador's large twin-peaked stratovolcano, ~50 km east of San Salvador, ~130 km3, no historical eruptions but recurrent deadly lahars, including the 2009 Verapaz disaster.
Sangay
Sangay is Ecuador's southernmost and most active stratovolcano, 5,286 m high in Morona Santiago province, in near-continuous eruption since 1628 and in an ongoing eruptive period since 2019, within UNESCO's Sangay National Park.
Santa Isabel
Nevado de Santa Isabel (Poleka Kasue) is an active andesitic dome-complex volcano in Colombia's Cordillera Central, 4,965 m high, in Los Nevados National Park, whose glacier has shrunk from 27.8 km² to 0.16 km² and is expected to disappear within about five years.
Seven Sisters Peaks
Seven Sisters Peaks: 2,747 m multi-summit massif in the Bulkley Ranges, British Columbia, above the Skeena River near Cedarvale; seven Tsimshian/Gitxsan-named summits, first ascent 1941 by Neal M. Carter, within Seven Sisters Provincial Park.
Sharks Teeth Peaks
Sharks Teeth Peaks, aka Shark's Teeth Peaks, is a 2,304 m ultra-prominent summit (1,914 m prominence) in the Kitimat Ranges, Coast Mountains, British Columbia, near Kimsquit Lake; first climbed July 2025.
Shedin Peak
Shedin Peak, a 2,588 m mountain in the Atna Range of the Skeena Mountains, northern British Columbia; its highest summit, 77 km north of Hazelton, with 1,798 m prominence.
Shiprock
Shiprock (Tsé Bit'a'í, the rock with wings) is a sacred volcanic neck on the Navajo Nation in northwestern New Mexico, a 30-million-year-old minette breccia plug about 600 m high with six radiating dikes; climbing has been banned since 1970.
Shishaldin
Shishaldin (Sisquk, Agajedan) is a 2,857 m symmetrical basaltic stratovolcano on Unimak Island in the eastern Aleutians, Alaska's Aleutian arc's highest peak, one of its most active volcanoes, with major eruptions in 1999, 2019-2020, and 2023.
Sierra Blanca
Sierra Blanca (New Mexico) is an eroded mid-Tertiary volcanic complex and massif in the Sacramento Mountains, highest peak of southern New Mexico at about 12,000 ft, sacred to the Mescalero Apache and home to Ski Apache.
Sierra Blanca Peak
Sierra Blanca Peak (White Mountain), 11,973 ft, Otero County, New Mexico; state's most prominent peak (5,533 ft), Mescalero Apache sacred mountain, home of Ski Apache.
Silverthrone
Silverthrone (Mount Silverthrone) is a remote 20-km-wide caldera complex and stratovolcano in the Coast Mountains of southwestern British Columbia, Canada, mainly erupted 100,000-500,000 years ago, with no known Holocene eruptions and a Moderate Canadian threat ranking.
Silvertip Mtn.
Silvertip Mountain, a 2,596 m ultra-prominence peak in the Skagit Range of the Canadian Cascades south of Hope, BC; most prominent non-volcanic Cascade peak, first climbed 1908.
Snow Tower
Snow Tower is a 6,572-foot summit in the Coast Range east of Juneau, Alaska (GNIS 1409827), first climbed June 8, 2015 by William Wacker and Mike Miller via the east face to east ridge.
Snowshoe Peak
Snowshoe Peak is the highest summit of the Cabinet Mountains in northwestern Montana, rising to 8,738 feet and anchoring the Cabinet Mountains Wilderness in the Kootenai National Forest.
Snowy Mountain
Snowy Mountain (Alaska) is a pair of glaciated andesite-dacite stratovolcanoes 15 km NE of Mount Katmai in Katmai National Park, 2,161 m high, with a Holocene debris avalanche, lava dome, and fumarolic, GREEN/NORMAL status.
Sollipulli
Sollipulli, a 2,282 m stratovolcano in Chile's Andean Southern Volcanic Zone between Llaima and Villarrica, holds a 4-km glacier-filled caldera of non-explosive origin, a VEI 5 Alpehué Plinian eruption about 2,900 years ago, and a rapidly thinning caldera glacier.
Solo, El
Solo, El (Cerro Solo) is a 6,205 m dacitic stratovolcano of nine eruptive centers on the Chile–Argentina border in the Central Andean Volcanic Arc, west of Nevados Ojos del Salado, with Holocene rhyodacitic pyroclastic-flow deposits and no dated eruptions.
South Sister
South Sister, highest peak of the Three Sisters volcano cluster in the Oregon Cascades at 3,157 m, a silicic stratovolcano built 50,000 to 2,000 years ago with ongoing uplift west of its summit.
Sovereign Mtn.
Sovereign Mountain (K'dalkitnu Dghelaya, Mount Sentry) is the 8,849-foot high point of the Talkeetna Mountains in Matanuska-Susitna Borough, South-Central Alaska, with 5,849 feet of prominence and 43.9 miles of isolation.
Spurr
Mount Spurr is a 3,374 m glaciated stratovolcano 126 km northwest of Anchorage, Alaska, whose Crater Peak vent erupted explosively in 1953 and three times in 1992; unrest in 2024-2025 ended without eruption.
Steens Mountain
Steens Mountain is a 9,733-foot fault-block mountain in southeastern Oregon, the state's highest point east of the Cascades, with glacial gorges, the 170,200-acre Steens Mountain Wilderness, and the 2000 CMPA.
Steller
Mount Steller is a 2,272 m glaciated Holocene-active stratovolcano in Katmai National Park, Alaska, between Denison and Kukak volcanoes; unmonitored, no historical eruptions, named 1928 for naturalist Georg Wilhelm Steller.
Stepovak Bay Group
Stepovak Bay Group: volcanic field of four Quaternary vents (Stepovak Bay 1-4) on the western Alaska Peninsula, SW of Kupreanof volcano; tholeiitic andesite, Holocene flows, GVP number 312055.
Sugarloaf Mountain
Sugarloaf Mountain (Pão de Açúcar), a 396 m gneiss monolith at the entrance of Guanabara Bay, Rio de Janeiro; a UNESCO World Heritage site reached by Brazil's first cable car (1912), with about 2 million visitors yearly.
Sumaco
Sumaco, isolated stratovolcano in Ecuador's Sub-Andean Amazon (Napo and Orellana provinces), 105 km east of Quito; alkaline back-arc volcano, potentially active, last confirmed eruption 1895, core of Sumaco Biosphere Reserve.
Taapaca
Taapaca (Nevados de Putre), dacitic lava-dome complex and andesitic stratovolcano, 5,860 m, NE of Putre, northern Chile; active 1.5 Ma, last eruption ~320 BCE, dormant but monitored.
Tacana
Tacana (Volcan Tacana) is a 4,064 m stratovolcano on the Mexico-Guatemala border, the northernmost volcano of the Central American Volcanic Arc; last phreatic eruption 1986, UNESCO biosphere reserve since 2006.