5 LINKS is a folding bicycle that can be ridden just like a regular bicycle but can be folded and unfolded easily. When it is folded, there is no need to carry it on one’s shoulders; it can be easily pulled and moved using its own wheels. It is easy to load on to public transportation such as trains, buses, airplanes and boats so that it is easy to travel to a wider range of destinations than ordinary bicycles can cover. Moreover, things can be carried on the bicycle rack while riding and also while it is folded and pulled or moved, so it can be used just like a traveler’s carrying cart. In short, it is a new mode of transportation designed in advance on the assumption it will be used with public transportation, and it is good for the health and also environmentally friendly.