The winner of a competition to design a new extension for Cheltenham's Art Gallery and Museum is due to be announced on Thursday.
The winning design is to be announced on Thursday
The extension is being built because of limited access to the collections and restricted exhibition and storage space at the Gloucestershire site.
Some of the existing buildings are to be knocked down to provide space for the new extension.
The winning design will be unveiled at the municipal offices at 1600 GMT.
A spokesman said: "The new facilities will enable the collections to be more accessible to the widest possible audiences, building on the Art Gallery and Museum's local, regional and national strengths."