M25 J17.

What is that new massive construction just south of J17 that has had the new slip roads constructed for it?

No real reason for asking, just being nosey.

It’s Carryfast’s new information HQ mate.

HS2 Concrete plant for making tunnel segments

Hs2 …its the start of the Chiltern Tunnel. The concrete plant is there to make the tunnel lining. https://www.hs2.org.uk/buckinghamshire-tunnels/

Ah, cheers. Bloody big place.

When they started, I wondered if it was a new service station.