Today many accidents occur because everyone is in hurry and we do not see the signal and crosses the railway line. So to solve this we can install this simple circuit which will give an red indicator when train is nearby and green indicator when train goes away from platform. For this we are using the reed switch as sensor.An indication of red and green light is done with the help LED. You can also modify this circuit to use bulb in place of LED so that it can be seen from distance.