A 38-year-old man has died after he fell from the second floor of the atrium of the Museum of Liverpool, Merseyside Police said.
Police were called to the museum at Mann Island just after 11am on Sunday and attempted CPR until paramedics arrived, but the man was pronounced dead a short while later.
His death is being treated as unexplained at this stage but it is not believed to be suspicious, police said.
The man's next of kin has been informed but formal identification has not yet taken place.
A post-mortem examination will be conducted to establish the cause of death.
Chief Inspector Jason Crellin said: "Our thoughts are with the family of the deceased and an investigation into the death is ongoing, although it is not believed to be suspicious.
"There were a number of people, staff and visitors, in the museum at the time and they are assisting with the investigation.
"We understand that this is a distressing situation for both staff and visitors, who may have been traumatised by the incident and they are advised to contact 111 or their GP for support.
"Emergency services personnel affected by the incident will be supported by their relevant organisations."
The Museum of Liverpool is closed and will remain closed for the rest of the day.