the City and South London Railway, opened in 1890, making it the world's oldest metro system. The Beijing Subway is the world's longest metro network at 879 km and the busiest one with annual ridership approximately 2.83 billion passenger trips. as of post=, 2024 the country with the most metro systems is China, with 54 in operation, including 11 of the 12 longest networks in the world.

Considerations