The London Underground, also known as the Tube, is a rapid transit system serving London and its surrounding areas. It consists of 11 lines and over 270 stations, making it one of the largest and oldest underground networks in the world. The stations vary in design, from historic buildings to modern facilities, and are crucial for daily commuters and tourists alike. Each station is identified by a unique name and often features iconic roundel signage. Many stations provide access to other forms of transport, such as buses and trains, enhancing connectivity throughout the city. The Tube operates from early morning until late at night, with extended hours on weekends.