I found the reference to this site in a report called "Danby Moors Archaeological Survey 1988-1989" (cheers Kat).
The site is described as an elongated mound (NE/SW) 19m long.
Fired up by this refence I was up at the mound today. The mound is quite easy to get to, it stands about 50m from the Danby Beacon road.
The mound is situated on the southern side of a shallow valley with views to the coast and Danby beacon.
The mound itself is curiously boat shaped with a depression on the top that echoes the shape of the mound, as opposed to your usual circular excavation pit. In paces I found it to be 23m long and 15m wide and orientated EEN-WWS.
There are a few rabbit holes in the mound which reveal the construction to be earth & stone.
Conclusion, not a spectacular mound but a definite NYM curiousity given it's shape, it may possibly related to the long barrow at Newton Mulgrave 7km away which is a lot bigger but of a similar shape and orientation.