Why are there stones between train tracks?

Answer

Hi Peter,

These stones mainly serve as ballast. Without these stones, the tracks would not remain in place when trains run over them. Certainly not in bends where the moving train tends to push the tracks in the direction of the outer bend. They also provide some cushioning and good drainage (better than, for example, a completely concrete bed where you would have to provide grids and drainage) of rainwater. “Repair” (read: extra stones and lay them back nicely) is also cheaper than concrete.

regards,
gert