Emergency services were called to the scene just after 5 pm after being alerted to the accident by a member of the public.
The man and woman are believed to have fallen onto or near the roof of one the entrances to the old German tunnel at the foot of the Railway Walk. The man was already dead when emergency services arrived.
The area was cordoned off as paramedics and specialist fire fighters treated the injured woman at the scene before she was taken to hospital.
The States Police are investigating the accident
• Full report in Tuesday’s Jersey Evening Post
