It's a bit weird

Returning from Manchester I stopped to take some pics of the edge of the City Centre, looking across the Middlewood site, which is going to be developed by the Scarborough group.

The light was fantastic. It is a very large site, what some might see as a very large area of wasteland (although interesting to see lapwings displaying here earlier in the year, so close to Spinningfields). The camera and lens I had could not really do justice to it. But walking a little way from where I had parked, and out of site of the road I saw this. Is it an art installation of some sort ? Is it a kids grotto ? Is it some kind of odd memorial ? Is it some strange bower (a kind of human version of something that an antipodean bower bird would construct) ? I haven't a clue. It's certainly enigmatic. And very odd.