There was a round cairn mentioned as being removed from the Burnden Park site when it was being developed at the beginning of the last century.
This is the Smithills harvest hill - http://www.themodernantiquarian.com/post/10559 - shouldn't be missed. I was brought up with the myth it was man-made; the archaeologist thinks it's a spoil heap.
Angles' ark Moor is huge and there is plenty to find there - in the peat. Can you see the Two Lads cairns from over there ? It's not unlikely there was a summer sunrise framed between them that was intended to be viewed from somewhere over there !