I rode this section in the summer of 2007 from south to north. From Massa Marittima, it starts out with some fairlt twisty bits before opening up into some classical Tuscan terrain as you approach Volterra. An enjoyable run!
OrsonRunning down past Pomaranace and Massa Marittima on the 439 towards Follonica is an interesting varied section that can be joined nicely to the 439d towards Volterra at the start or the 441 east at the end.
BBR-David