Fes, like many Moroccan cities, carries a moderate level of risk with it. It's considerably safe for tourists during the day, particularly in busy, populated areas. However, caution needs to be taken against pickpocketing and small scale crimes. The culture can be a bit of a shock, especially with unwelcome attention and catcalling, so it's important to dress modestly and be aware of your surroundings. At night, it might be best to stick to well-lit and crowded places, or use a trusted taxi.