> It is true what you say and demonstrated by where the TBM will inevitably start - at the London end. The only significant tunnelling is at the London end, an

> It is true what you say and demonstrated by where the TBM will inevitably start - at the London end. The only significant tunnelling is at the London end, and in the Cotswolds. It doesn't really make much sense to begin in the middle. The approach to Birmingham will be almost entirely on the surface.