Here’s a fantastic old map of the first segment of Hong Kong’s now extensive rapid transit system. The original source dates the map to 1978, which seems reasonable to me – the route was well under construction at that time, with the segment from Kwun Tong to Shek Kip Mei opening in October 1979. The route was extended to Tim Sha Tsui in December of that year, and the initial section was completed in February 1980 when the extension to Chater station (now Central station) opened. There are are couple of other changed station names as well: “Argyle” is now Mong Kok and “Waterloo” has become Yau Ma Tei. The Prince Edward infill station is also absent, as it wasn’t opened until 1982.

Interestingly, the changing colour of the route line doesn’t indicate subterranean/at-grade segments of the route as I first thought: it’s just a by-product of the two-colour printing used for the map. There are only two inks used here – blue and brown in various tints – and the dark brown route line is actually a combination of the blue and brown inks overprinting each other. The brown ink has been removed where the white roads are, but the blue ink remains, giving the effect seen here.

Source: Thestandnews.com