This route starts in a car park in South Walsham but you can pick it up anywhere on Fleet Dyke. Unfortunately, you can’t do this if you are mud weighting in the Broad. 😀
It is 4.7 miles and will take around one and half to two hours depending on your speed and how many stops to take in the scenery.
You will need a free weeks trial to download the gpx file but you can print the route at https://osmaps.ordnancesurvey.co.uk/route/5790337/202008132.