The Beijing Subway is the rapid transit system of Beijing Municipality that consists of 24 lines including 19 rapid transit lines, two airport rail links, one maglev line and 2 light rail lines, and 428 stations. The rail network extends across 12 urban and suburban districts of Beijing and into one district of Langfang in neighboring Hebei province. With 3.8484 billion trips delivered in 2018, an average of 10.544 million trips per day, the Beijing Subway is the world's busiest metro system. Single-day ridership set a record of 13.7538 million on July 12, 2019.