Plastic bottle caps - for a garden path, this is a very practical option. After all, plasticity is not afraid of high humidity, and it will not receive stress from temperature extremes.
This idea has one frightening detail: the number of caps. From the photo it is clear that there are a lot of caps, besides multi-colored, so that the patterns turn out to be diverse and beautiful. But where to get so many? The construction of the track may even slow down due to the difficulty of solving this problem.
But the idea is quite possible to realize, if you connect to the process all relatives, friends, acquaintances, neighbors. In this case, one summer season may be enough to build such a track.