Britain is building one of the world’s most expensive railways

The bits that have really cost have been going through the Cotswolds where local opposition has meant insane planning applications and eventually a decision to bury the lines in tunnels. It was totally unnecessary and could have gone above ground if we had a more sane planning system, something the new government has promised to at least try and change (I suspect they will fail…)

The Chilterns, I think, and burying the line in tunnels was more or less necessary anyway. Some of the tunnels could technically probably have been replaced with cuttings, but apparently it would've cost more. The existing line used them mostly because tunneling was a lot harder back then. Mostly, the NIMBYs seem to have forced the existing tunnels to be longer than they need to be, which is expensive but not making building infrastructure in the country entirely non-viable levels of expensive.