Long Valley Caldera
Long Valley Caldera is a volcanic depression in California northeast of Mammoth Lakes, known for skiing resorts, geothermal features, and a spectacular resurgent dome.
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Geography
| Address | Long Valley, near Mammoth Lakes, California, USAState Route 203 |
|---|---|
| Continent | North America |
| Region | Western United States |
| Subregion | Great Basin |
| Country | United States |
| State | California |
| County | Mono County |
| District | Long Valley |
| City | Mammoth Lakes |
| Neighborhood | Long Valley |
| Postal Code | 93546 |
| Timezone | AmericaLos Angeles |
| Latitude | 37.6 |
| Longitude | -119.02 |
| Maps |
11:53 AM LOCAL TIMELong Valley Caldera is an enormous volcanic depression roughly 20 by 11 miles (32 by 18 km) in California, just east of Mammoth Lakes and the Sierra Nevada crest. The caldera formed about 760,000 years ago after a massive Mono eruption that produced the famous Lake Mono and thick rhyolite flows; subsequent resurgent uplift has raised the caldera floor by over 30 meters, creating the broad, flat basin and the prominent Devil’s Postpile engraved on its eastern rim. Visitors come for geothermal areas with hot springs and fumaroles, year-round skiing from resorts like Mammoth Mountain and June Mountain, and access to trails for hiking, biking, and wildlife viewing. The caldera’s high-elevation basin is also a gateway to Yosemite and the Eastern Sierra, making it a key regional transit point and a dynamic landscape of volcanic relics, alpine lakes, and changing seasons.
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