I have just read an old post re Spion Kop , like many readers I too have wondered where Spion Kop was . With reference to Mark Bau's VictorianRailways.net South Kensington page diagrams and photographs.
There is a photo of an Up Hitachi set approaching Moonee Ponds Creek Junction , and in the background is what I know as the Flyover which takes the BMS Sub lines from the Through Suburban Lines to Kensington. This Flyover is now officially named Spion Kop , which was for many years it's unofficial name.
Reference to Dia 11/23 South Kensington the Goods Lines Arrival and Departure , Dia 5/71 Essendon Suburban , Main Goods, West Tower , Dia 4/83 Main Goods, West Tower, Broadmeandows Suburban , all show this bridge / flyover but no reference to the unofficial name .
The original Spion Kop in South Africa when the two day battle took place and was a major military disaster for the British Army , took place during a very cold and unusual heavy snowfall. The Flyover / Spion Kop was high, flat and cold hence the nickname.
The disaster at Spion Kop , South Africa was reported by that famous reporter and later Prime Minister Winston Churchill who was captured by the Boers at Spion Kop and later escaped to file his report. As a result the disaster became a major scandal and remained in the public conciousness for many years after. A number of Football ( soccer ) stadiums in England have or had exposed hillsides known as either Spion Kop or the Kop, Liverpool probably the best known. Hope this is of interest,