The Lee quarry trail can be found in Rossendale (Lancs.).
We decided to visit it with a friend who is local to the area and know it well. Starting in Ramsbottom. We rode for quite a few miles to make it part of our ride.
There is a red route with a black section added on.
It's mainly straight forward easy type riding, but I'm not good on technical stuff and walked a tiny secton on the red.
Just be aware that there were alot of undesirable people around today (probably due to the hot weather) who were really rude to us. Also came across one woman walking her 2 dogs on a tricky downhill section. It isn't like the normal trail centres. There are no facilities and we found it hard to find. Also the slog up to the start was off putting, mainly because today was warm.
There were quite a few riders by the time we left, many were kitted out in full downhill body armour, but that's up to them.
However there seems to be scope in the quarry itself to do your own trails, maybe adding on bits here and there.
It was fun and we ended up doing the red trail 3 times. 
If you're local it's worth a visit.