Fears have been voiced that the largest local authority-led road construction project in the country could wipe Holt off the map.

The town's deputy mayor, Councillor Michael Hill, spoke out after plans for the Norwich Northern Distributor Road (NDR) were revised - and block off the B1149 Holt Road at the Drayton Lane turn-off.

He claimed motorists could struggle to find the picturesque town - popular with the Royals - when the new route is completed.

However, roads chiefs have argued that a new roundabout link to the NDR will actually improve connections and ease congestion.

Mr Hill said: 'My biggest concern is how will Holt be identified for people coming out of the city – how will they find us?

'I can see that it will be signposted to Cromer or Great Yarmouth but I can't see it signposted to Holt.

'The town could be seen as being obliterated by these signs.'

Costing £178.5m, the NDR has been dubbed a 'road to nowhere' by critics and faced a legal challenge last year.

But Norfolk County Council argue it will bring a huge economic boost and transport improvements.

Work began on the road late last year and it is due to open in February 2018.

John Birchall, NDR Public Liaison Officer, said: 'At the moment the B1149 Holt Road joins Cromer Road at the existing roundabout, but this causes morning peak queues on the A140 because the B road traffic has priority. Holt Road traffic then adds to the A road traffic heading into Norwich, with regular congestion at the Boundary and on Fifers Lane and Norwich Ring Road.

'With the new road layout, the A140 will go over the NDR, with a roundabout each side and on/off slip roads. Early designs had Holt Road connecting at the north roundabout, but this has been changed to simplify and improve the overall operation of the junction, and so as not to recreate the existing problems for A140 traffic, with all the B road traffic having to go through this junction, and having priority at the roundabout.

'Instead of connecting at the A140/NDR junction, the B1149 will connect via a realigned and improved Drayton Lane. There will be a roundabout on Holt Road, connecting to a big NDR roundabout, and continuing to another small roundabout on Reepham Road.

'So traffic leaving Norwich on the A140 and heading for Holt will be able to follow signs on to the NDR, turning right at the Drayton Lane roundabout, re-joining the existing B1149 at the new roundabout on the southern edge of Horsford.'

He added: 'A significant further benefit of this arrangement is that the improved Drayton Lane, with roundabouts on Holt Road, the NDR and Reepham Road, will improve important connections between Horsford and Drayton. The remaining stretch of Holt Road will be closed off and will only serve the properties along there, with a turning head at the end. Holly Lane will be reduced to a cycle link.'

Motorists travelling from Holt to Norwich and elsewhere will also benefit from the new road layout, it is claimed.

Mr Birchall said: 'Traffic from Holt heading towards Norwich will be directed on to the NDR, and off at the A140 junction. But not all the Holt Road traffic will do this.

'The NDR will offer better options for a significant proportion of the traffic that would have used Fifers Lane and the Ring Road to reach destinations to the north and east of the city, and onwards towards Gt Yarmouth. This traffic will be able to stay on the NDR and leave at whatever connecting roundabout suits them best, or go all the way to the A47.

'This will take pressure off other roads. The forecast for opening in 2017 is a 3,600 vehicle a day reduction on the A140 just north of the Boundary junction, 1,400 reduction on Fifers Lane and 3,900 reduction on Mile Cross Lane.'