may 23, 2008. Two SNCB/NMBS series 55 enter the last part of the route to Aachen West, comming from Montzen. They are now running at idle because once the Gemmenich tunnel is passed, the tracks slope down 2,5 percent towards Aachen West. Later this couple of locomotives returned to Montzen with a heavy train consisting of scraped metal. See this video on youtube. Photo: jeronimus567c