I’m interested to know if your supersolution gives you a landmark plus distance and direction leading to the spot to dig? That’s the assumption that is much discussed, but in my opinion even this level of detail has issues. For instance if the instruction is dig 5m from the war memorial, the landmark could be a fair size monument, so is it the middle or an edge? And it might not be clear if it’s 5m from the step at the bottom of the monument or the main statue/pillar structure. If we start to look at things this way, accepting a need for a clear named feature, it rules out huge areas of France public land. There surely has to be some very small, clearly named, feature to form part of the supersolution instruction. There are very few of these features in forests for instance, and anything suitable such as a standing stone or statue is likely to be busy with tourists.