there is a table which illustrates the relative data about underground system in six countries, london, paris, tokyo, washington d.c, kyoto and los angeles. in 1983 the first railway was built in london, which is the longest railway (1100km) in the six cities. the carrying capacity reach 548 million people per year. as a countries having railway earlier, paris established the first underground in 1890 and 850 million people per year were carried by using 548 kilometer railway. comparatively, tokyo has relatively less railway (149 km), but it carries most people per year about 1434 million people. similarly, the railway in los angeles is used effectively. people in los angeles use 14 km railway to carry 306 million people per year when it was built in 2001 firstly.