The interior of Rama is essentially a large cylindrical landscape, dubbed "The Central Plain" by the crew, 16 kilometres in diameter and nearly 50 long, with artificial gravity provided by its 0.25 rpm spin. It is split into the "northern" and "southern" plains, divided in the middle by a 10-km wide expanse of water the astronauts dub the "Cylindrical Sea". In the center of the Cylindrical Sea is an island of unknown purpose covered in tall, skyscraper-like structures, which the astronauts name "New York" due to an imagined similarity to Manhattan. At each end of the ship are North and South "Poles". The North Pole is effectively the bow and the South Pole the stern, as Rama accelerates in the direction of the north pole and its drive system is at the South Pole.