Essential maintenance will be carried out on the linkspan at the Symbister ferry terminal in Whalsay early next month.
Shetland Islands Council says the maintenance will involve major structural work, which will result in the linkspan being taken out of use.
Vehicles will be unable to use the ferries which will operate only for foot passengers during this time. They will also run to the winter timetable.
The service will be affected form 7.30pm on Friday 1st April to 6am on Monday 4th April, weather permitting.
That means the last service to take vehicles to Symbister will be the 6.30pm from Laxo, while the last service to take vehicles to Laxo will be the 7pm from Symbister.
Access for foot passengers will be via a gangway from the vessel to quayside in Symbister, and via the ramp at Laxo.
Any passengers who may require assistance are asked to make themselves known to the crew.
Online bookings for this period will be suspended, although foot passengers are encouraged to book through the booking office.
The work forms part of the council’s ongoing linkspan replacement programme, that has also seen similar work on ferry terminals at Skerries and Vidlin.
It follows work on the Ulsta linkspan on Sunday night.
Shetland Islands Council has apologised for any inconvenience that these essential works may cause.