Yes - I'm not saying that there is nothing older under Merlin's Mount.. I am saying that mottes have been built on low land by rivers. Maybe it is Silbury's baby brother with or without spiral paths. I just happen to favour the idea of it being a motte to defend the river at Marlborough - 'cos that's what it looks like if you ignore the Capability Brown type landscape terraces. Not going to fall out with you, baza. You could be right and as Nigel says - let's see some evidence 'cos all else is speculation based on personal opinions and perspectives.