For RailFans, the Journey itself is the Destination. - Sreerup Patranabis

#FAQ
What does the number painted on a white stone besides rail tracks signify?
Answer-
As shown in the picture the number signifies the gradient on the rail tracks to help the loco pilot. The arrow shown indicates whether it is Up or Down gradient. Sometimes 'L' is written on it indicating a Lower gradient ahead. This is information is handy for the...
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loco pilot to decide accordingly and ensure smooth running of train.
200 number on the stone denotes 1 meter down gradient for a distance of 200 meters. Do check such stones while train is moving through ghat section.
Please be very careful while railfanning or doorplating. Safety is foremost, rest all is secondary.
Hope the information helps.