It would be a shame to overshadow them as they are ultra practical with varying sizes depending on the cravings: sometimes small as a handbag or vast such a larger hiking. First of all, we advise you to study your needs. Do you plan to take a computer? Your phone ? Special accessories? Little or a lot of clothes? Depending on your answers, you will opt for a model with more or less specific compartments. Note that some versions have elastic on the front in order to slip a cardigan or a scarf. A real plus in summer. As for urban walks, indulge yourself with really stylish colors. For example, timeless black.