Wylfa Newydd: What will power tunnel under Menai be like?

A tunnel carrying power under the River Thames in central London is to be replicated under the Menai Strait in north Wales.

Last year, National Grid said it would use underground cables instead of pylons between Wylfa Newydd nuclear power station, on Anglesey and the Gwynedd mainland.

The tunnel under the Menai Strait will be shorter than the ones in London, but larger inside.

BBC Wales' Nick Palit ventured inside one of the tunnels to look around.