Of note: Every other SPG property in the UK offers universally-accepted King sized beds (76x80).

At the GNH, they offer UK King beds (59x79), or actually smaller than a US Queen (60x80).

I recognize that this is a US-centric view of the world, but pretty much every western chain (and even independent...) hotel centers around the sizing of the US King bed.

Be warned if you're there with more than just yourself, it could be quite cozy depending on your size.