More than 50,000 people have now signed a petition calling for the Wells Harbour Railway to be saved.
Ashley Illingsworth, from Nottingham, said he was stunned by the support shown since he started the petition on change.org on May 1.
Mr Illingsworth, 34, said: "I really didn't expect that many. When I started the petition I was hoping at the most for 500 and thinking how amazing that be, so 50,000 is unbelievable. I just hope people will listen."
The narrow-gauge railway which runs from Wells town towards the beach is expected to close later this year after more than four decades in operation.
Its owners, Gary and Alison Brecknell, announced last year they wanted to stand down in the "in the next year or two" and asked the landowners Holkham Estate for a new 10-year lease in order to sell the equipment to a new operator.
But a spokesman for Holkham said such a renewal would not be "ideal" as the area's needs were evolving. Neither Holkham, nor Mrs Brecknell, said they wanted to comment on the petition.
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