Metropolitana

Fast, if limited, form of transport
Noteworthy for: Part of the reason the metro is so underdeveloped is that each time the local government tries to expand it, another incredible archeological discovery is made, halting development.
Word to the wise: Don't forget to validate your ticket by punching it in one of the yellow machines at the metro station.
Look out for the large red M sign to spot entrances to the metro, which is by far Rome's fastest means of transportation. There are currently only two lines: A and B. Orange Line A connects north-west with the south-east, passing important stops for the Vatican Museums (Cipro), the Vatican (Ottaviano) and the Spanish Steps (Piazza di Spagna).
Blue Line B connects north-east with south-west with stops for the Circus Maximus (Circo Massimo) and the Colosseum (Colosseo). All lines intersect at the main station Termini. There are other rail services operated by ATAC as well, including the Roma-Lido line, which connects Rome to the sea at Ostia.

You can buy tickets at news-stands, stations, tabacchi (tobacco shops) and occasionally from a station manager. If you need the metro to reach central Rome then it is worth getting either a booklet of tickets or a tourist pass BTI (EUR 16.50) for three days of unlimited travel.

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