Object lessons Behind the scenes of a museum's grand reserves

A tour of the newarchive collection of London's Science Museum andits associates reveals a cornucopia of wonders and treasures

- Rowan Moore

Museum storage facilities are unseen wonders, dark troves of material in little-publicised locations. They might hold 95% or more of an institution's collections, with some objects as fascinating and beautiful as those on view, others acquired for longforgotten reasons, destined to languish on obscure shelves. They offer resources for researchers, content for exhibitions, and refreshed permanent displays and refuge to artefacts with nowhere else to go. They are necessary backup to the workings of a museum. They are the underwater part of the iceberg, the paddling parts of a swan, the dark side of the moon.

Now, three of the UK's most significant reserve collections are being rehoused in multimillion-pound facilities where, as well as being better cared for, they will be more accessible to the public. This shift has been prompted by a government plan, announced in 2015, to sell Blythe House in west London, an Edwardian baroque office block converted in the 1970s into a store for the British Museum, the Victoria & Albert and the Science Museum. The first of these has moved its objects to a new archaeological research collection in Shinfield, a village 40km west of London, and the second to the V&A East Storehouse, a "new kind of museum experience", which will open next year within the former 2012 Olympics media centre in east London.