When officials in Utah on Monday revealed they had found a shimmering, metal structure deep in the Red Rock desert, they refused to say exactly where.

They hoped that would be enough to deter amateur adventurers from setting off to find it, risking getting dangerously lost in the process.

But there was little chance that people would abide by this advice. By Wednesday, pictures were emerging on Instagram of people triumphantly posing with the monolith, eager to show the world that they had got there first - even if the wider mystery of why it is there remains unsolved.