The trust, which owns Belton House, and highways officials are considering closing Five Gates Lane, connecting Londonthorpe Lane and Belton village.

The trust owns the land and the county is responsible for maintaining the road.

They say safety concerns and an accident in May 2007, in which two young men were killed when their car hit a tree, has led them to consider options for the "future safe use of the road".

The road bisects the Belton estate, separating the house from Bellmount Tower - a landmark which is owned by the trust and can be seen from miles around.

Hundreds of cars use the road every day to access the A607 towards Lincoln or to go into Alma Park, diverting them from already congested routes like Manthorpe Road and the High Dyke.

The trust has written to parish councils, emergency services, other landowners and the Woodland Trust, which owns woodland adjacent to the estate, informing them of the plans.

A spokeswoman said: "We are in the very early stages of exploring options for the future safe use of the road by vehicles.

"Because of the high volume of cars using the road, an increasing number of accidents and the double fatality last year, clearly we need to look at this.

"We are very mindful that we want to take into consideration the thoughts of key stakeholders, which is why we have consulted them.
"There are no immediate plans to go beyond that in terms of consultation, but if any decision was taken which involved statutory processes then a public consultation would be part of that."

Closing the road would have a huge knock-on effect, with traffic forced to use already congested routes in and out of Grantham.

Chairman of Grantham Road Users and Londonthorpe parish councillor Nick Craft would oppose any plans to close the road.

He said: "If it is made into a cycle and pedestrian only route that would mean more traffic on the Belton Lane and Manthorpe Road junction.

"I would sooner see Five Gates Lane widened and made into a proper roadway - it's certainly not a road that wants closing."

The move could also affect businesses in the Alma Park area.

Belton Park Golf Club's general manager Steve Rowley said: "It would be a tragedy to close that road.

"It's not the best road in the world but two cars can pass down it quite easily.

"For a lot of our members and people on Alma Park it cuts out what can be really nasty traffic jams on Manthorpe Road and Belton Lane.

Engineering firm Parker Hannifin, based in Londonthorpe Lane, said the closure would be "inconvenient but nothing too drastic".

Londonthorpe and Harrowby Without Parish Council has said it cannot support the idea and Belton parish council will discuss the issue at its next meeting on August 7.

• The National Trust says they are considering the future of Five Gates Lane because of a high number of accidents on the road.
  
  Lincolnshire Road Safety Partnership has confirmed there have been four accidents in the last three years.
  
  The latest was in May 2007 when friends Dean Chevalier, 20, and Matthew Prothero, 23, died when the car they were travelling in hit a tree.
  
  There was a serious accident in 2005, which means at least one person involved suffered life-threatening injuries.
  
  There were two minor accidents - one in 2005 and one in 2006.
  
  Would you support a move to close Five Gates Lane? Or do you think closing the road would place an unacceptable burden on other routes in the area? Click here to e-mail your views.