North Sister is a prominent volcanic peak located in the Cascade Range of Oregon, USA. It stands at an elevation of 10,358 feet (3,192 meters) and is part of the Three Sisters volcanic complex, which includes Middle Sister and South Sister. North Sister is known for its rugged terrain and distinctive jagged summit, making it a popular destination for experienced hikers and climbers. The mountain is primarily composed of basalt and andesite rock, formed from volcanic activity over millions of years. North Sister is considered dormant, with its last known eruption occurring around 2,000 years ago. The surrounding area is rich in biodiversity and offers stunning views of the Deschutes National Forest and nearby peaks.