An A&E worker visiting from Liverpool was bewildered to find he had been hit with an £100 fine after unwittingly stopping in a private car park.
Tom Moore, 58, was visiting a friend he used to work with at the Norfolk and Norwich University Hospital in late December.
He briefly parked at the St Augustine's Gate Car Park which is located just off Waterloo Road on December 27.
The car was parked for 12 minutes while he nipped out to find a cash machine around 5pm.
Mr Moore then received a letter from National Parking Enforcement on January 5 stating he had parked in a private car park.
His parking charge notice would be reduced to £60 if paid within 14 days.
The walk-in centre agency worker recalled the car park being free for the public to use 30 years ago.
Mr Moore said: "I only saw the sign after I had driven past. You literally have to look sideways to see the private land signs. I did not see it at all."
The Liverpool-born father-of-one appealed against the parking charge notice but was informed it had been rejected on Thursday afternoon.
He said he was threatened with "debt recovery agents" if he did not cough up the funds.
Mr Moore added: "The car park is very badly signed and does not meet British Parking Association standards.
"It is not that I can't afford £100 or £60 but I want to make others aware of this car park. I am concerned if a student or someone who can ill-afford to pay gets caught out like me.
"If you are a complete stranger or it's the first time you park there then there is no real indication it is private. It should be barriered or card-entry.
"They are covertly dragging you into that car park then entrapping you. All of a sudden you owe £100."
Julie Lecaille, director of National Parking Enforcement said: "I’m not going to comment as yet.
"If Mr Moore has further questions regarding the signage, he should take his appeal to the Independent Appeals Service as advised on the latest correspondence he received."
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