Hachures, the short radiating lines cartographers used to indicate slopes or depressions, suggested something worth noting at ground level, though the map offered no further explanation. When the site was inspected in 1984, that cartographic curiosity resolved itself into something altogether more mundane and yet strangely evocative: a disused gravel pit, roughly twenty-five metres across and three metres deep, its edges softened by decades of encroaching trees and bramble.

Gravel pits of this kind were a quiet but essential part of the rural and agricultural economy throughout the nineteenth and early twentieth centuries. Local material was extracted for road surfacing, drainage work, or building projects, and once exhausted, these workings were simply abandoned to the landscape. The Charlestown pit is thought to date from that period, making it a modest but legible trace of the working countryside rather than anything monumental. What gives it a particular quality is the gap between what the map implied and what the ground revealed, a reminder that even routine cartographic symbols carry their own small mysteries until someone goes to look.