I visited the Wuppertal Schwebebahn whilst on holiday... interesting for about one or two stations, then a bit tedious really. But they do curves without needing superelevation - the car body simply swings out to the appropriate angle.
However... signalling. The system seems to be controlled by 2-aspect colour lights without repeaters, but all the signals seem to have a 3rd aspect that I never saw lighted. Does anyone know what the 3rd indication is? (Mostly the sections are platform starter to platform starter, uncertain whether there's any kind of overlap, but there are a few of the longer sections with a mid-section signal, again seemingly standard 2-aspect but with a 3rd indication.) The big question in my mind is just how they operate the signals? Track circuiting would appear to be rather difficult with just one rail mounted on that huge steel "track bed".)
Finally, all signals seemed to have ERTMS-style reperes (yellow arrow rather than triangle on blue background) associated with them. So are they installing ETCS? Or do they fulfil some other function? (Each repere carried the same number as the nearby signal.)