Harwell to Wantage through Ginge?

I’m not sure if I’m seeing your route correctly, but I have a few thoughts. If you are not in good shape I would not recommend trying to cross Ginge Brooke on Ickneild Way. In anything other than (persistently) perfectly dry conditions it becomes so deep in thick sticky mud that it is almost unpassable going Eastwards.

To be honest I’d stick with the published 544 route, it is quiet and actually rather pleasant! Enjoy!

Don’t do it! Trust route 544. Your proposed route has a chest-high locked gate at the end of Hillside, a muddy track (although currently fairly dry) past Aldfield Farm, then after Newbury Road a very rough section of Icknield Way currently with side-to-side puddles. And the proposed right turn after crossing Ginge Brook uses a private track. The Icknield Way does continue west after Ginge Brook but it’s very cut up by horses; can be OK-ish to cycle eastbound in dry weather, but westbound is uphill and pretty difficult.