Is there a countryside code leave nothing but footprints take nothing but photographs who said this?

SLOGAN FOR CONSERVATION OF HILLS AND FORESTS Yes, I had seen a hoarding having this slogan/code at Nilgiris Range of hills saying that: "LEAVE NOTHING BUT FOOTPRINTS

TAKE NOTHING BUT MEMORIES" I was very much impressed by this couplet because it tells the tourists not to leave any wastes or any material which is foreign to the forest environment and not to take anything belongs to the forest because for the sustainability of environment. Sorry, I don't know who said this but hats off to the creator of this slogan/code !