Join us today for a hilly circular walk around the valley of the By Brook in Wiltshire. Climbing immediately from the stone cottages of Box, we gain the first of today's many views. After a close encounter with Hazelbury Manor we cross the line of Brunel's famous Box Hill tunnel deep in the hillside beneath us. Appropriately, a couple of well-placed GWR benches give the opportunity to catch our breath and enjoy the view. From Box Hill we descend all the way to the meandering By Brook and it's impressive weirs. What goes down must go up! Climbing again we reach Thickwood, perched at the head of it's own valley - our most northerly point. Between Colerne and quaint Ditteridge we'll enjoy a full 365 degree view - unusual from such a lowly hill. Finally, we cross both Brunel's railway and the By Brook once more on our return to Box.