Main access is down the airshaft about 60ft (10 fathom) and requires rigging off a couple of old scaffold poles. This gives access to a small area of interesting workings, I'm convinced a bit of digging would reveal more in here and there certainly are some tempting looking dive spots :lol:
On the hillside there are some walk in adits but I haven't found anything hugely interesting.
It was a huge mine, a quick Google earth and you can see it dominated the landscape around for a large area with a labyrinth of leats and interesting surface features. It's all private land belonging to the farm so this needs to be kept in mind with regards to exploration, the hillside is also very open and any attempts at gaining access need to be kept discreet and respectful.
The old copper mines of snowdonia is well worth a read, it has output figures for the copper mines and Drws y Coed along with Llanberis and Lliwedd was the most productive of them all.