I'm a native to the Ypres region. Here we still have hills retaining their names given during WW1: Hill 60, Hill 62, Hill 41,...
I did some research on the naming of the hills. And during my research I found a similar practice during WW2, Korean war & Vietnam war. For earlier & latter wars, I couldn't find trustworthy examples.
Who's idea was it to designate hilltops with names referring tot their height & when (which war) was it first implemented?