Stage B05 from Gorizia to Castelmonte was, for us, 35 km long and had less than 1000 m uphill and almost as much downhill. Without the lift the total ascent would have been 300 m longer, which fits the description in the guide book. The total length of the stage is about 48 km, so we recommend hitchhiking, public transport, cutting it short or using shortcuts.
