The people are standing on Small Bridge being amazed by the wooden structure of Mathematical Bridge which links the two halves of Queens' College across the River Cam.
The 'student accommodation' pic is actually the library of Darwin College - I don't think any of it is student rooms. One of the nicer examples of 1970s (?) architecture in Cambridge, I think. Incidentally the old part of Darwin (just visible on the left) was owned by Charles Darwin's family.