Mexico City's subway system is a wonder to behold. Its 12 color-coded lines ferry millions of visitors and commuters to most parts of the city quickly and efficiently, often much faster than traveling overland in the city's notorious traffic; rides cost MX$5. You can buy single-ride passes and transport cards at ticket windows at each station, but lines can be long. A better bet is to load up your card with credit at automated machines located at Metrobus stations. Metro stations are marked with graphical icons—a grasshopper, a fountain—as well as written names, in response to the city's relatively high illiteracy rate at the time of the system's construction. The metro has a reputation for being uncomfortably hot and sardine-packed during rush hour; women traveling solo may want to take advantage of the women-and-children-only cars, located at the front of each train. A recent government crackdown has reduced the number of mobile vendors that roam the cars hawking anything from socks and cigarette lighters to pirated CDs for MX$10, though you'll probably encounter a few. Keep a close eye on your belongings at all times while entering, exiting, and riding the metro, and avoid using it late at night.