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The world's busiest station, in terms of daily passenger throughput, is Shinjuku Station in Tokyo, Japan. Ikebukuro Station, just minutes away, is the world's second-busiest.
The world's largest station, in terms of floor area, is Nagoya Station in Nagoya, Japan. However, the Nagoya Station complex incorporates two office towers and an underground shopping concourse, so the railway terminal itself is not large in comparison to others. Shinjuku Station is the second largest. In terms of platform capacity, the world's largest station is Grand Central Terminal in New York City, USA.