Remarkable old images are on display along with other memorabilia and some recently unearthed plans that illustrate some key features.
Railworld organiser Brian Pearce said: “We are still adding to it as we go along there is so much stuff that we have got.
“It’s absolutely fascinating stuff and we are improving it with more exhibits all the time.
“Some of the old plans are remarkable. We have found one plan from the 1840s that is in colour and around 3m long detailing the old Peterborough East railway station, the city’s first station.
“There are also plans of a railway dock that once stood on the bank of the Nene. We believe trains brought coal to be loaded on to barges and incoming barges brough fruit and produce to be loaded into rail wagons. There are very few records of this old dock area.”
The exhibition is open every day between 10.30am and 4pm until September 1 when it wil be open during those hours every Wednesday and at weekends.