I wouldn't plan a trip around a visit to Beanley plantation but it's well worth seeing if you're coming to see The Ringses or any of the other sites close by.
The site itself is unmistakable on Google Earth as a circular area in the planation has been left clear to preserve the site.
To access the site from Eglingham, take the road West towards Beanley, passing The Ringses site on the left as you climb the hill. Turn left at the first junction and you will quickly see a gate to a field with ample space for parking on the left hand side. Enter through the gate and follow the wide farm track up the slope to the South East. As you climb up the track there is a large ditch and very prominent rock outcrop on the right. OS maps show a footpath leaving this track on the right near this point, passing to the west of the site, but I couldn't see any sign of this on the ground. Visited in late July, any area not covered with trees was thick with waist high ferns, so a path could be there, I just couldn't see it. Instead, follow the farm track up the hill, turning right and coming to a junction on the left. The easiest way into the site is to head West-South-West from this junction for about 100m, through thick pine forrest with some undergrowth (fairly flat and dry but not the easiest going) till you see the clearing ahead.
Before leaving the plantation you will encounter the first ring ditch, very clear on the ground but hard to photograph under the canopy of trees. A few more steps and you come into the clearing. Different from all the iron age hill forts/defended settlements I've visited so far this site has no dramatic views over open country-side. The sense of enclosure however is dramatic on a still day and has a strong effect on the atmosphere of the site. Just standing and listening to the wind through the trees and distant bird-song has quite an effect. The clearing itself is about 55m across, but given the inner ditches the habitable area is probably less than this.
Unfortunately when I visited, the whole site was covered in waist to shoulder high ferns so any detailed survey of the inner ditches wasn't possible. A quick trip into part of the centre showed there was at least one large ring ditch inside the outer, wooded ditch. It's quite easy to follow the ditches round the whole site but be careful if following the outer ditch in the plantation as it's very easy to lose your bearings (as I did). I'm planning to visit the site again in winter to get a better idea of any central structures.
The outer ditches feel defensive in nature and the site is on the highest ground around, sitting above The Ringses. The North and West of the site is very steeply sloped and would offer good defense but the East and South is quite flat, so the "fort" nature of the site would be hard to justify. That being said it's obviously a much more defensive position than others close by.
Archaeologia Aeliana 1822 mentions the site and the impressive nature of the access road. With that in mind I retraced my steps looking for more features.
The rock outcrop passed on the way into the site is well worth a few minutes as you head back. The ditch between the track and the outcrop is very deep and errosion has exposed what look like hand laid stones, forming an impressive entrance of some kind? The ditch certainly looks far to big to be there just for drainage. I could see no evidence of rock art on the outcrop itself, but the sides facing West and North have very impressive holes on their sides. Quite possible these at naturally formed, I don't know enough to say but they certainly catch the eye.
There is a Cist nearby in the plantation but I was unable to locate it on my first visit.
Other items of interest very close by are:
1) An large circular enclosure (45m across), 170m north of the access road and 130m east of the main road - not visited yet but clearly visible on google earth.
2) Cup and ring stones, all removed unfortunately (Alnwick Castle Museum), references N3151, N3163 & N4368 on Keys to the Past.