A Jonson Clarke-Harris brace either side of half-time saw Posh battle back to earn a 2-2 draw.
Our photograph David Lowndes took these pictures of some of the crowd, but do you know anyone pictured?
Take a look and tag in anyone you know on social media.
Get full reaction, and more Posh news, here.
21. Posh 2 Barnsley 2
Peterborough United fans during the 2-2 draw with Barnsley. Photo: David Lowndes
22. Posh 2 Barnsley 2
Peterborough United fans during the 2-2 draw with Barnsley. Photo: David Lowndes
23. Posh 2 Barnsley 2
Peterborough United fans during the 2-2 draw with Barnsley. Photo: David Lowndes
24. Posh 2 Barnsley 2
Peterborough United fans during the 2-2 draw with Barnsley. Photo: David Lowndes
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