Full permission has been given to demolish the existing buildings at Leale's Yard off the Bridge and put fences around it.
Leale's Yard is a large brownfield site off the Bridge, equivalent to the size of more than four football pitches, and is owned by the CI Co-Op.
It's lain derelict for years, but this week planners have given the go ahead to get rid of the remaining buildings. Some have had roofs removed already.
The Co-Op has teamed up with Omnibus Investments to deliver the development.
The vision is for more than 330 flats, retail space and parking.
The States are looking at flood defence work along the inner harbour wall to protect Leale's Yard and to invest in the project as part of a strategy to provide more essential housing, mainly in the north of Guernsey.


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