"The route starts direct from Newark Northgate station, and is traffic-free all the way to the village of Cotham. It follows the trackbed of the old Newark to Bottesford railway, closed in the 1980s, and provides a welcome green corridor between the two communities as an alternative to busy roads."
National Route #64
The section I did was only a short reccy from Hawton Lane to Newark Station. Even in that short two mile route on Easter Sunday, it was surprisingly pretty, sided in two places by large ponds. The daffodils pleasantly in bloom in the March sunshine. The route was busy being used by walkers, runners, cyclists and families. Good metalled track for the part I did.
More details of this Rail Trail can be found at:
http://www.sustrans.org.uk/ncn/map/route/newark-to-cotham
There is also a handy PDF leaftet:
http://www.sustrans.org.uk/sites/default/files/documents/newark_to_cotham.pdf