Paris Passengers carried per day: 4.4m Cost of ticket: 80p flat fare Length: 131 miles    Lines: 14   Stations: 297 In Paris there are pleasures for those who use the Metro  -- many of them artistic. The graceful Art Nouveau dragon-fly entrances are just the most noticeable on a Metro system which celebrated its 100thanniversary by spending 30 million francs (PS2.9million) on making its stations works of art. On my way home I pass Bonne Nouvelle station in the heart of Paris's cinema district. There, during the cinema festival this summer, special lighting effects dot the platforms and films are projected onto the large advertising boards. More than anything the metro is efficient. "When I worked on line 4", says a retired driver, "we had exactly 30 minutes and 15 seconds to complete the journey. If it took any longer, they cut our pay." But there are problems. Many Metro stations have too many stairs, and changing lines at big interchanges  can be tiresome. Moscow Passengers carried per day: 9m Cost of ticket: 12p Length: 164 miles    Lines: 11   Stations: 162 The first underground passage for the Moscow Metropolitan started in 1932. Three years later the trains started running. They haven't stopped since-- every 90 seconds or two minutes during rush hour, every five minutes the rest of the time, from 6 a.m. till 1 a. m. There may be a crowd of people but there is seldom a wait. The trains take you through spacious and spotless stations. For tourists it's a major sightseeing attraction: from Russian Art Deco to neo-classical, the Metro stations are not to be missed. Tokyo Passengers carried per day: 7m Cost of ticket: 90p ~ PS1.68 Length: 177 miles    Lines: 12   Stations: 209 Trains do not just arrive on time in Tokyo. They stop right on the platform mark so that passengers can line up knowing exactly where the doors will open. Train driving is a respectful job for life, for which the applicants must pass a strict screening of health checks, interviews and written exams before they can put on the enviable uniform, cap and white gloves. However, overcrowding means it is far from perfect. At rush hours, some stations employ part-time platform staff to push in passengers. Carriages can be filled to 184% of capacity . The main reason for such conditions is that the Tokyo subway station system has only 15 miles of track for every 1 million people, compared to 36 on the London Underground. New lines are under construction, but at a cost of PS500,000 per meter of rail. Progress has been slow. Mexico City Passengers carried per day: 4.2m Cost of ticket: 11p flat fare Length: 99 miles    Lines: 11   Stations: 175 Fast, relatively safe, and very cheap, Mexico City's underground is an ideal place of order and efficiency compared to the disorders above. The Mexican capital's underground system is the biggest in the continent and one of the most subsidized   networks in the world. The first trains leave the station at 5 a.m. and the last after midnight as the crowd move from the outskirts of the 20 million-strong megacity  . Mexico City's Metro also attracts a sizeable group of passengers who are unwilling to spend hours in traffic jams. There is a master plan to build new lines and extend existing one, but financial constraints   complicated by the fact that the system runs through different jurisdicitons   mean progress is slow. In which two cities can travelling by underground be a sightseeing experience?
Moscow and Tokyo Paris and Moscow Paris and Mexico City Tokyo and Mexico City