This one used to be mine, it was on a nature reserve at Morgan’s Hill, near Calne, the one day I went up there for a walk, and it had disappeared! It was leaning forward a bit, but nothing that a bloke with a posting spade and several lengths of rebar couldn’t have fixed, but either Wiltshire Wildlife who oversaw it and decided it was a hazard, or someone took a shine to it and nicked it! It would have required some considerable effort either way.
Still makes me sad, it was a nice place to sit, the view is fantastic; on a clear day you can see must of the edge of the Cotswolds, from just north of Bath to up near Stroud, and beyond that, if you know where to look, you can see the Brecon Beacons and the Black Mountains, including Sugarloaf.