In fact, there is a scientific reason behind the presence of these stones on the railway track.

Apparently, the railway tracks looks very simple, but in reality it is not so simple.

Between the steel railway tracks are planks made of concrete or wood called sleepers.

Underneath and in between these sleepers are stones called ballast, under which there are 2 more layers of soil, followed by the general surface of the earth.

We think that the track is laid on normal level but it is not true, if you look closely, these tracks are slightly higher than normal level.

The trains used in countries like Pakistan weigh millions of kilograms and this load cannot be carried by the track alone.
The stones spread all over the track help in this task and are of a special type that do not move from their place even with the vibration of the train passing by.

If normal stones are used, they will shift due to the passing of the train which may cause the track to dislodge.

If you see a train passing on the track, you will see that the stones spread there do not move from their place while also keeping the planks in place, thus the track easily carries the load of the train.

There are a few other reasons for using these stones.
When the train passes, the movement of the train also creates vibrations that can cause the track to spread, the effect of these vibrations is reduced by these stones.

Similarly, if these stones are not present, the concrete sleepers cannot remain stable and as a result the track can be very difficult to support the weight of the train.

And yes, if these stones are not there, grass, plants and trees can grow on the track, which can make the train difficult to travel, but these stones do not allow any kind of greenery to grow.
Due to these stones, the rain water does not stand on the track but goes underground.
This method has been used for many years and is still proving to be very effective.