The slip, just below the Chain Bridge Honey Farm, occurred at about 7am on Saturday, and a substantial footbridge recently restored by the county council and several mature trees were swept into the River Tweed below, while a section of the road has also collapsed.
The road below the honey farm is now closed to traffic and pedestrians until the route is repaired and made safe, but the bridge is open to traffic and pedestrians from the Scottish side.
Willie Robson, owner of the Chain Bridge Honey Farm, emphasised that although the road to the chain bridge is closed, the honey farm is still open for business as usual. And, although he was concerned by the landslide and the time the road will be closed for, he believes it should be relatively easy to repair.
Edward Cawthorn, who lives at Chain Bridge House, said: "It has completely swept away the footbridge from the riverside path, which was only just restored some six weeks ago. The riverside is impassable from the bridge to Horncliffe."
Mr Cawthorn added that a crack has appeared in the surface on the opposite side of the road to that which subsided, and the section of road that has collapsed was newly laid with Tarmac following a repair to a small hole about eight weeks ago.
A Northumberland County Council spokeswoman said: "The C2, Horncliffe Road near Union Chain Bridge has been closed on an emergency basis due to a landslip. The road became dangerous to motorists from December 7 and will remain closed until further notice. A regular temporary road closure order will be expected to be in place for in excess of six months."