The Alster is a large lake located in the city of Hamburg, Germany. It is formed by the Alster River and serves as a popular recreational area for both locals and tourists. The lake is surrounded by parks, walking paths, and cafes, making it a vibrant spot for outdoor activities such as jogging, cycling, and boating. The Alster is divided into two main sections: the Inner Alster and the Outer Alster. The Inner Alster is smaller and more urban, while the Outer Alster is larger and features more natural landscapes. The lake is also known for its picturesque views and is a central feature of Hamburg's scenic beauty.