Greenberfield Locks, in Barnoldswick, is the first feature on the canal as it passes from North Yorkshire into Lancashire.
The top lock marks the start of the highest stretch on the canal's 127 mile path (480ft), which lasts until the descent starts again at Barrowford. The pumphouse here is one of the points along this stretch which helps keep the canal topped up; the water travels all the way from Winterburn some 8.5 miles away.
This cache has a 4 star difficulty, due to the abdundance of Ivy around the hiding area, meaning it might take multiple attempts to find.
To reduce the number of DNFs, I have now added a spoiler picture.