The Picasso Museum in Paris has closed its doors for two years while the building undergoes a £17.6m renovation to increase its size.
The museum houses a 5,000-strong collection of paintings, drawings, sculptures, ceramics, photographs and documents charting Picasso's career.
But only a fraction can be displayed at any one time due to space restrictions.
Museum director Anne Baldassari said: "It needs modernising... We can't continue like this."
The museum, in a baroque mansion in Paris' Marais district, opened in 1985, and it traces the Spanish-born artist's prolific career from its beginnings in the 19th Century to his death in 1973.
Renovation of the 3,000-square-metre space will begin early next year, with the gallery due to re-open in February 2012.
The move will see the museum's available display space doubled and the exhibition and visitor areas remodelled.
In the meantime, the artworks will be packaged and shipped, under tight security, to storerooms managed by the national museum authority, Ms Baldassari said.
The museum will also stop lending out works during the overhaul, so the inventory can be updated.
The museum will continue to host education and cultural events related to the Picasso collection at other sites while the renovation is done.