One caution about the metro line between Pireaus and downtown Athens. We really like this line because its cheap, fast, and pretty convenient. But, unfortunately, many gypsies and other street thieves also know that this line is convenient. The line is often a popular place for very skilled pickpockets and groups of gypsies. These street crooks will not physically harm you, but they are very good at their craft. Make sure you carefully protect your purses and wallets and do not let anything distract you from being alert. This is a good practice for anywhere in Europe, but on this particular line all your antennae should be operating at full throttle.