So, from Ugley, head to Elmdon as you have planned but turn right down towards Ickleton, left to Duxford, cross the A505 (easy on bikes as there is a traffic island), up through Wittlesford, Little Shelford, Great Shelford.
Just after crossing the railway tracks in Gt Shelford there's a cyclepath on the left that takes you across the fields all the way to the back of Addenbrookes, much nicer than any of the roads into Cambridge. Funky DNA pattern painted on the surface too.
The A10 into Cambridge isn't the nicest route, if it were me I'd use the top end of this (Done this route about 20 times now):-
http://www.bikely.com/maps/bike-path/71351
So, from Ugley, head to Elmdon as you have planned but turn right down towards Ickleton, left to Duxford, cross the A505 (easy on bikes as there is a traffic island), up through Wittlesford, Little Shelford, Great Shelford.
Just after crossing the railway tracks in Gt Shelford there's a cyclepath on the left that takes you across the fields all the way to the back of Addenbrookes, much nicer than any of the roads into Cambridge. Funky DNA pattern painted on the surface too.