Several vintage signs have been stolen from the Watercress Line in Hampshire.
The authentic advertisements were taken from Ropley Station over the Jubilee weekend, just as the charity announced it had been given the Queen's Award for Voluntary Service.
The metal signs were displayed around railways and volunteers say they play an important part in the railway's history.
In a post on Twitter, the Watercress Line warned that the signs might be put up for sale online or through railway auction sites.
People are being urged to look out for them.
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