We have Cromwell Nature Reserve. It basically extends between the North Cut Locks (by Avocet,,going WSW ending at Cromwell Bottom. In essence it fills the space between the canal and the river Calder.
A map of the reserve is available from at https://www.calderdale.gov.uk/v2/sites/default/files/cromwell-bottom-poster_0.pdf The map shows the paths available. They differ in quality,
The path first leaves the canal towpath immediately beyond the lock at North Cut, Turning left, going over toward the river bank, this first part is at best very underdeveloped, but is definitely a path. There are bits where it almost disappears into the river, where it suddenly goes up a small bank, has an occasional fallen tree or low overhanging branch. Whatever else, it almost guarantees some good mud. Some would describe it as urticatory (well nettled). It is no more than a few hundred yards, and ends as it meets the path proper.. You can tell. a few steps rise to your right.
The next path leaves the canal towpath two hundred yards or so after the North Cut locks. It is just before the first proper large tree. There is a place where you scramble up. The path is clear but unconstructed. It climbs about six foot, and the path then goes across the top of a bank between the various ponds. There are one or two other similar but lesser entrances. They go nowhere. If you do not immediately see that you have a bank extending before you, you have the wrong climb. The surface is uneven, but clear and runnable. It is not long,but serves well to avoid the worst of the first path (which it meets). Descend onto the first path and turn right.
The third is found by running from North Cut along the towpath to the next lock, just past which is the first proper gate. Go through then very shortly after, turn left. The path is now better, but still quite uneven and at one point crosses a short bridge, then getting to the short range of steps down to the end of the first path. Turn right.
The next bit of the path continues from the bottom of the steps to the right. From now on the path is much better made, and nearly all wheelchair friendly-ish.. It reaches a point where it meets another path with an old industrial bridge crossing the river Calder.
It is worth noting that this is a nature reserve. It is still developing as such, and parts are still just a little murky, but please recognise that it is such and deserves an associated respect. I do not say that we should not use it, but just not to do anything which might damage it. On the map, you will see a bird feeding area at No 1. If you are runnng at a time when people might be bird watching, it might be easily avoided by taking the path over the top of the bump. It may not be a big contribution, but we can try.