CONGRATULATIONS to your wife on her retirement! Have you been to Cambridge before? I lived not far from there! If you have a chance, definately take a punt ride on the River Cam. Very enjoyable! Gee, while your there, take a side trip to Hemmingford Abbots/Hemmingford Grey. Nice quaint little villages! Also of interest not far away is the town of St Ives. They have one of the chapels in the middle of the bridge! You can get the key to go inside from the Norris Museum on the week-end. Oh, also nearby is Buckden Towers!
Hope you both have a lovely week-end! Look forward to hearing your thoughts on the area!