When we tried to find the trail Levada da Norte, that passes under the ER105 near Boca da Encumeada (we didn't realised that until some french people told us with better informations then our map), we decided to go to Levada da Serra and it was super beautiful! There were a lot of rocks that fell down and waterfalls that end up on the actual trail (so prepare to get wet), but it is a really nice little climb to get to the the plateau: at the end to the levada da Serra you will switch on Bica da Cana trail to get to the Plateau where you'll see the "Parques Eolicos do Paul da Serra", which is really nice and flat ^^... for once!