Prague, as any larger, cosmopolitan city, has its problems with pickpockets. Please, leave your expensive jewelry at home, bring only what you need and leave some of that in your hotel safe. Always have a copy of your passport in another place, away from the original. In case of loss, replacement is much easier. Walking around town, watch yourself and loved ones and do not “offer” your belongings to the criminals by carrying your wallet in an easily accessible place such your back pocket or an open purse. Best are your purses or bags that allow you to carry your valuables under your clothing. Be especially careful in places where many people converge in a small space such as in front of the Astronomical Clock, other crowded tourist areas or tight shopping places. The subway (metro), the streetcar or the bus is especially susceptible to this as people stand very close together!