Nice afternoon so out for couple of hours exercise on the bike mapping around south Cheshunt. Surveyed a new roundabout on Lt Ellis Way that I didn't even know about. Will add to map untagged, with note to FIX as soon as it is open.
Also can add a new dimension to the bridge/viaduct saga. On way back followed the towpath of the canalised River Lea as it crosses the M25. This is just to west of the A10 junction. It crosses the motorway in an aqueduct but to all intents and purposes is a tunnel at the same time. It disappears "underground" and is covered over in such a way that the towpath is actually on top of the canal itself for a short while. Not sure how I will tag it - probably as canal + bridge, with a note to say that it is "undergound".