frogstudio Posted August 26, 2009 Hi to all train geeks. If got some simple question. When travelling in the subway, I always notice these small little signs (see pics). Tey have different numbers, letters and dot patters. Has anynone any idea of what they are for and where I can find reference on them? Many thanks. Share this post Link to post Share on other sites
WesternOutlaw Posted September 7, 2009 I wonder if they're some sort of mile markers. Share this post Link to post Share on other sites
