IT may surprise many people, but a watchdog group wants to save the 1930s extension to the Co-op building in the centre of Huddersfield.

It's forlorn and boarded up and looking distinctly tatty.

Many people pass by without giving it a second look.

Yet to the Twentieth Century Society it's a bit of a gem.

In fact, the history lovers label it one of the best inter- war buildings in Huddersfield.

Now, they are calling for it to be listed.

The property at the corner of New Street and Castlegate has been empty since the Heaven and Hell nightclub closed last December.

It is for sale and the London-based Twentieth Century Society believes it could be in danger of "insensitive" changes.

Cordula Zeidler, a caseworker for the society, said: "There is an obvious risk of major alteration to the building which, though it is in a conservation area, is not listed and is therefore not fully protected."

The building was opened in 1936 and built to designs by architects W A Johnson and J W Cropper.

Its supporters view it as an impressive example of modern architecture designed and built between the wars.

Ms Zeidler said: "The building is faced in local stone and it shows influences of avant-garde European buildings of the time, namely those of Erich Mendelsohn and Dutch architecture of the era.

"The building dominates its location, a prominent corner site, and represents a successful and mature archi- tectural focus for the area, similar to the equally well-designed Co-op building in Bradford, also by W A Johnson."

The Twentieth Century Society said it was of equal quality to the recently listed Huddersfield Public Library and Art Gallery building.

Ms Zeidler added: "The exterior of the building is a very fine example of a 1930s departmental store, where the new architecture of the time has been applied effectively.

"The society believes it deserves protection, as one of the best inter-war buildings in Huddersfield."