Tokyo Subway. Its colourful map may look like a messy plate of yakisoba (fried noodles), but Tokyo's subway is relatively easy to negotiate. There are two systems, the eight-line TRTA (which stands for "Teito Rapid Transit Authority", but is also referred to as the Eidan) and the four-line Toei, run by the city authority, which also manages the buses and the tram line. The systems share some of the same stations, but unless you buy a special ticket from the vending machines that specifies your route from one system to the other, you cannot switch mid-journey between the two sets of lines without paying extra at the ticket barrier. Subways have connecting passageways to overland train lines, such as the Yamanote.
You'll generally pay for your ticket at the vending machines beside the electronic ticket gates - apart from major stations (marked with a triangle on the subway map), there are no ticket sales windows. If fazed by the wide range of price buttons you can choose from, buy the cheapest ticket and sort out the difference with the gatekeeper at the other end. You must always buy separate tickets for subways and overland trains, unless you're using an SF Metro or Pasunetto card .
Trains run daily from around 5am to just after midnight, and during peak daytime hours as frequently as every five minutes. Leaving a station can be complicated by the number of exits (sixty in Shinjuku, for example), but there are maps close to the ticket barriers and on the platforms indicating where the exits emerge, and strips of yellow tiles on the floor mark the routes to the ticket barriers.
The cheapest subway ticket is ¥160 and, since most journeys across central Tokyo cost no more than ¥190, few of the travel passes on offer are good value for short-stay visitors. However, if you're going to be travelling around a lot, it makes sense to buy kaisuken , carnet-type tickets where you get eleven tickets for the price of ten - look for the special buttons on the automated ticket machines at the stations. Off-peak tickets give you twelve tickets for the price of ten, but can only be used 10am to 4pm weekdays, while Saturday/holiday tickets give you fourteen tickets for the price of ten. Handiest of all is the SF Metro Card , or Pasunetto Card , which saves you no money, but can be used on both Eidan and Toei subways and all the private railways (but not JR) in the Tokyo area. As you go through a ticket barrier, the appropriate fare is deducted from the card's stored value; these cards can be bought from ticket offices and machines, and also used in machines to pay for tickets. If you're here for a month or more and will be travelling the same route most days, you might buy a teiki season ticket, which runs for one, three or six months, and covers your specified route and stations in between.