The tabular graph compares the subway system in six metropolises in the field of the opening date, its length and annual ridership.
Overall, it is clear that the three oldest underground systems are larger and serve significantly more passengers than the newer systems.
London’s s belowground system was incorporated in 1863 having the longest route of 394 km and carries 775 million passengers annually. Two subway systems were inaugurated in Paris and Tokyo during the first half of the 20th century. Although the length of the route of the pairs’ system is half than London, it carries far more passengers. Tokyo’s system serves the largest number of passengers at 1927 million.
During the later period of the 20th century, subterranean systems were opened in Washington DC and Kyoto. The latest network was in Los Angeles opened in 2001. There is only 29 km of difference between Washington DC and Tokyo, Whilst the number of travellers is much less in Washington DC. Kyoto and Los angles have the shortest route and serve the least number of passengers with 45 and 50 million respectively.