Tazawa-ko is a picturesque lake located in Akita Prefecture, Japan. It is known for its stunning blue waters and is the deepest lake in Japan, reaching a depth of 423 meters. Surrounded by mountains, the area offers beautiful scenery and various outdoor activities, including hiking and boating. The lake is also famous for its legend of Tazawa-ko, which tells the story of a beautiful girl named Tazawa who fell in love with a young man. Visitors can enjoy the serene environment, explore nearby hot springs, and experience the local culture, making it a popular destination for tourists.