Police were called to Lendal Bridge in York in the early hours of the morning.
Officers were on the scene at 3.03am where a man was found with serious injuries at the bottom of the steps on Dame Judi Dench Walk.
The 25-year-old man from London has been taken to Leeds General Infirmary where he remains in a critical condition.
Lendal Bridge is currently closed whilst police conduct an investigation to determine the full circumstances.
Anyone who witnessed anything which would be helpful to the investigation is asked to contact police.
Over 28,000 drivers have applied for refunds after being wrongly fined for driving across Lendal Bridge in York.
New figures show the majority of drivers fined were visitors to the city.
Around 56,000 fines totalling £1.3m were handed out during a trial to tackle congestion.
City of York Council has refunded nearly £700,000 since the restrictions were ruled unlawful.
The national Traffic Penalty Tribunal ruled last spring that the council had no power to issue penalty charge notices for using Coppergate and Lendal Bridge.
The driver who challenged the penalty imposed by the City of York Council after he drove along Coppergate says he is delighted that his appeal was upheld.
The decision has called in to question more than a million pounds worth of fines imposed by the authority to motorists for using the route, as well as crossing Lendal Bridge.
The Traffic Adjudicator says the council had no authority to fine drivers, but the council have warned drivers the restrictions and fines will remain in place.
Nigel Rhodes says he is pleased with the outcome of his case.
A successful legal appeal against a traffic fine has brought more than a million pounds worth of similar penalties into question.
Nigel Rhodes is the first driver to successfully appeal against a ticket for contravening traffic restrictions on Coppergate.
More than fifty thousand drivers have so far been fined for using Coppergate and Lendal Bridge during the daytime.
But the Traffic Adjudicator now says City of York Council had no power to issue the notice to Mr Rhodes.
The Council says it is seeking legal advice over the ruling and that restrictions remain in place, meaning drivers could still be fined.
Drivers in York are accusing the council of milking them for cash, after dozens of them were caught out by new restrictions on Lendal Bridge.
For the next six months anyone driving over the bridge between 10.30 in the morning and five in the evening will be fined 60 pounds.
York City Council says the move was well publicised locally - but tourists have continued to use the bridge, unaware of the new restrictions.
Watch the full report below.
A new scheme to restrict access to Lendal Bridge in York has caught out scores of drivers on its first day.
For the next six months anyone crossing the bridge between 10.30 in the morning and five in the evening will receive a £60 fine. York City Council say the move will reduce congestion, but residents are accusing them of making drivers into a cash cow.
Lendal Bridge in York will be closed to cars during daylight hours from today. It's part of a trial to improve pedestrian access around the Museum Gardens and the Minster.
No vehicles other than buses, taxis and bicycles will be able to cross the bridge for six months.
City of York Council also hopes to create a relatively traffic-free corridor running from Holgate, past the railway station, across Lendal Bridge and up Museum Street, St Leonard’s Place and Gillygate all the way to Clarence Street and beyond.