Building works at the Bristol Royal Infirmary will block access to the main entrance for the foreseeable future.
The hospital's main entrance will be closed while works are carried out to replace the automated doors, installing a new revolving door and side entrance instead.
Patients and visitors will be signposted to another nearby entrance to get inside, while the main entrance is closed.
Works began yesterday (Monday, July 13) and are not due to be completed until Friday, November 20.
The entrance leads to the Welcome Centre reception and waiting area, which will both be unaffected by the temporary closure of the doorway.
University Hospitals Bristol NHS Foundation Trust, which runs the hospital, opened the £5m Welcome Centre in 2013.
The project aimed to transform the entrance into a bright and spacious area, with shops and cafes including Costa and Boots.
Fewer patients and visitors have been filing into the hospital's doors as a result of the coronavirus restrictions, but more routine operations and treatments are likely to resume in the coming weeks and months.
Adult inpatients at any of the trust's hospitals are currently only allowed one visitor per day.
Visitors must be a named close family member or friend, and must present a letter from the trust at reception, in which they are named as the agreed visitor.
Further guidance on the trust's website states: "Anyone not carrying a letter will be politely informed that they are not permitted to visit.
"A single visit per adult inpatient is permitted a day by their nominated family member or friend.
"This single visit per day can be between 15 minutes and up to a maximum of two hours depending on the patient's condition."
Anyone entering the hospital also has to wear a face covering or mask at all times, in line with the government guidance which came into force on June 15.
