There are not believed to be any casualties and residents were warned to keep their doors and windows closed, emergency services said.
Cambridgeshire Fire and Rescue Service posted images showing around eight trailers completely gutted by fire at around 9pm, around two hours after they were called to the incident.
Peterborough police asked people to stay clear of the area and said temporary road closures were in place in Shrewsbury Avenue, Morley Way and Celta Road.
They added: “It is expected emergency services will be working late into the night to tackle the blaze.”
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