This one in Boystown, County Wicklow, does the opposite: it is entirely invisible to anyone walking across it. The only way to see it at all is from the air, where a cropmark, a subtle variation in vegetation caused by buried features affecting how plants grow above them, traces the outline of a small oval structure roughly ten metres by five metres on a steep west-facing slope.

What the aerial photographs reveal is the ghost of a hut, its shape preserved not in stone but in soil. Alongside the oval outline, there appears to be the possible arc of a fosse, a defensive or boundary ditch, curving away to the south-west. The combination of a small enclosed oval and an accompanying ditch is consistent with early medieval settlement patterns found elsewhere in Wicklow and across Ireland, though without excavation the precise date and function of the Boystown site remain open questions. The site sits on ground that would have offered a commanding westward prospect, which may explain why someone chose it, even if the slope made building there a more demanding proposition.