Ada County is located in the southwestern part of Idaho, USA. It is the most populous county in the state, with its county seat in Boise, which is also the state capital. The county covers an area of approximately 1,100 square miles and features a mix of urban and rural landscapes. The county is known for its outdoor recreational opportunities, including hiking, biking, and fishing, thanks to its proximity to the Boise River and the surrounding foothills. Ada County is also home to several parks and natural reserves, making it a popular destination for residents and visitors alike.