A woman is in a stable condition after suffering serious head injuries in a crash with another cyclist on Victoria Avenue.
It happened at high tide during Storm Eunice, with waves crashing over the sea walls.
Ambulance crews were called to the crash on the cycle track, near lay-by three, at around 7:30pm on Thursday 17 February.
The injured woman, who is in her 50s, was taken to A&E and then transported to Southampton Hospital for treatment.
Jersey Police say she's receiving 'ongoing support'.
The other cyclist was treated at the scene for minor injuries and didn't need to go to hospital.
Officers want to speak to anyone who saw what happened or who may have helped the two cyclists.
Anyone with information is asked to call police on 612612, quoting M01123/2022.
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