An own goal from Lloyd Jones gave United the derby day honours and three more crucial points.
Our match photographer David Lowndes captured just some of the fans in the stands in this gallery.
Take a look and see who you can spot.
And you can get all the latest Posh news, here.
1. Posh 1 Cambridge 0
Peterborough United fans enjoy the 1-0 win over Cambridge United. Photo: David Lowndes
2. Posh 1 Cambridge 0
Peterborough United fans enjoy the 1-0 win over Cambridge United. Photo: David Lowndes
3. Posh 1 Cambridge 0
Peterborough United fans enjoy the 1-0 win over Cambridge United. Photo: David Lowndes
4. Posh 1 Cambridge 0
Peterborough United fans enjoy the 1-0 win over Cambridge United. Photo: David Lowndes
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