Idaho became the 43rd state in 1890 and is nicknamed the "Gem State". It has many natural resources and unspoiled scenic and natural areas. Some of the more famous rivers are the Snake River, Salmon River, Clearwater River, Boise River, and Payette River. One of the many attractions in Idaho is Hells Canyon that the Snake River flows through. Hells Canyon is popular for its rapids, fishing, and camping during the summer months. The climate in Idaho varies from one part of the state to another and is influenced by the maritime climate of the Pacific Ocean. One important sources of income for Idaho is its agriculture. Idaho produces about a third of the potatoes in the US. Another less known fact is that Boise has become a leader in semiconductor manufacturing.