Work will start on a £19 million historical records office.
A turf cutting ceremony will be held on Friday at The Keep in Woollards Field, Moulsecoomb, Brighton.
It will mark the start of construction on the site, which is being jointly funded by East Sussex County Council, Brighton and Hove City Council and the University of Sussex and is due to open in 2013.
The centre will house more than 900 years of historical resources and collections in six miles of archives.
The ceremony will be held from 10.45am.