reduke

Hi There, I am always curious when I see an alignment on Google maps that looks like a disused railway - be it a cutting, line of trees etc - to find out what it was and it's history. However, I came across something that looks very much like this in north London, but can find no evidence on-line that anything was there. Any idea what this is/was? I have marked what I can see here: https://mapsengine.google.com/map/edit?mid=z6H5aOjUtn2o.kygJs1MAQVlA The northern end I am not so sure about, but the cuttings/alignment for the rest look far too uniform to be a coincidence. I was wondering was it a rail line, canal, old road etc?