Medium: Pen and ink on paper
The chalk range of the Chiltern Hills reaches its highest point at Combe Hill, near Wendover, at the bottom left of this plan. Roughly drawn interlining ('hachuring') in black depicts relief with a recto inscription in pencil noting that "the irregular pencil lines are drawn too strong". The draughtsman has described earthworks, barrows, minor tributaries and a navigable feeder of the Grand Union Canal and a section of the prehistoric Icknield Way running from above Tring to "Pittlesthorn". Corrections in red ink are clearly visible, possibly dating from the 1831 revision of the plan.