Punting on the Cam

	It can get very crowded on the Cam at times

We take a trip up the River Cam through the heart of Cambridge, with the famous colleges on the left (apart from St John's) and the Backs on the right. In the course of the trip we sail under St John's Bridge of Sighs (copied from the more famous one in Venice), pass Trinity's Wren Library (designed by Sir Christopher Wren), sail under Clare Bridge (one pier of which has sunk, providing a practical illustration of just how much you can distort a stone arch without endangering the structure) and finish our trip at the Mathematical Bridge which was built without a single nail or other fastening. Alas, over the years the once stiff joints have loosened up and the beams are now held in place very firmly with some substantial bolts.