Finished work early around lunch time and met up with a friend at Abiko station and went for a roundabout ride.
From home, down the Edo river to the Tone-Unga canal. Followed that to Tone river to Abiko and up to the station. From the station we headed straight down to the Tega-Numa (swamp) lake and went counter clockwise around the lake and headed towards the the Tone river. My friend departed East to Narita and I ventured West and decided to explore a new way home. My Garmin though was missing the vital maps so I had to judge where I was and follow the sunset a bit till it got too dark. Once I hit route 6 near Toride I went up the Kokaiwa river to Moriya and it got very dark, then to Kokinu to route 3 which was a straight ride home. My Garmin maps kicked in though and I could easily get home in the end. Was hard keeping out of the way of traffic on the dark unlit country roads with trucks trying to get back from their shifts. Quite surprised how far I went. The Kokaiwa river was very nice and I may even go back again tomorrow to see it in daylight.
Here is the route as I remember it. Not sure of the roads around Moriya. Will double check that later form the Garmin which only recorded the last hour of the journey.