"Good Lord, I never knew that was here!"
That, according to John Murdoch, director of the Courtauld Institute Galleries, is the reaction of every other visitor to the gallery when they find a treasury of Impressionist and Post-Impressionist paintings, including old friends such as Van Gogh's Self Portrait with a Bandaged Ear and Manet's A Bar at the Folies-Bergere.
Now, suddenly and potentially controversially, the calm and studied quiet surrounding the galleries could be rudely interrupted by plans for an on-the-cheap concert hall.
The galleries - un-signposted in the Strand, London, because of Westminster Council and English Heritage restrictions - are to close for a year for a lottery-aided renovation which will include air conditioning, and better lighting for the pictures, and extra space to bring unseen Tintorettos and other Italian masterpieces from the vaults.
The galleries are set in William Chambers' magnificent 18th-century courtyard. And it is in here that even more dramatic changes are afoot. First, thanks to a campaign by The Independent to remove parked cars from cultural spaces, the Inland Revenue, which is housed in part of Somerset House, encircling the courtyard, will ban its staff from parking cars there. The Revenue is slow to embrace change and the ban, although not in force yet, is coming.
The second change is more significant; a plan to build a concert hall in the courtyard. This plan, which has had no official public airing, was outlined by Lord Rothschild, the chairman of the Heritage Lottery Fund, at a private dinner party attended by Chris Smith, the Secretary of State for Culture, and his permanent secretary, Hayden Phillips. Lord Rothschild described an idea for a 400-seat concert hall underground in the vaults, costing about pounds 20m, and an alternative proposal to cover the Great Quadrangle with a removable acoustic shell, equip it with a stage and seating at a strikingly cheap cost of under pounds 1m.
Lord Rothschild, as Heritage Fund chairman, can approve the money for such a venture, but cannot himself make the application. However, the newly formed Somerset House Trust, headed by Sir Timothy Sainsbury, can, and sources confirm that the move is being considered.
There is, though, a rather large snag - one that could lead to a falling out among the cultural establishment. Between the Inland Revenue and the Courtauld Institute Galleries is the Courtauld Institute itself - the world-famous centre of study for art historians. Strike up the band and the band could disturb an academic seminar on post-Impressionism.
Mr Murdoch chooses his words carefully, but nevertheless signals the potential problems. "We [the Courtauld Institute Galleries] are unmistakably and will always be the principal high culture attraction for Somerset House ... Jacob Rothschild has suggested some of the pavilion under which concerts could take place. Students at the Courtauld Institute have to work and have meetings. The strains of beautiful music wafting across the neo-classical facades we would greatly enjoy - at lunchtimes and in the evenings. But common sense says that at other times there would have to be restrictions."
Lord Rothschild's office said it was too early to talk about programming, but the idea would be for music to be played "at reasonable times".
The new face of Somerset House and one of London's great architectural spaces would not end in the Great Quadrangle. Beyond that is the most exciting hidden treasure of all.
The building at the south of the Quad now houses the family courts. Creep through this building and one sees a boxed- in stairwell (boxed-in literally because of fears that people emerging from the courts might be tempted to commit suicide) and through a door marked No Members Of The Public Beyond This Point Please, one can just glimpse what Mr Murdoch calls "the greatest staircase in London". Designed by William Chambers, the Navy Staircase is a series of flying arches with asymmetric curved flights arranged around an oval, crossing and criss-crossing a central space.
Outside the building is probably London's most appallingly unused space - a 160-yard terrace overlooking the Thames, empty and again barred to the public. A real case of "Good Lord, I never knew that was here".
But the courts are moving out. The building could become an extension for the Courtauld Institute galleries, the perfect place to display their Impressionist paintings. The river frontage could buzz with people.
Mr Murdoch and I stood along on it. It is for the Somerset House Trust to say whether the soon-to-be-empty building will become a riverside art gallery. But Mr Murdoch's eyes brightened at the possibility. "It would be a way of giving the river back to London. It's been a hideous waste. But imagine; the lights dancing on the leaves of the Plaintrees. People ambling and drinking on the animated terrace in Parisian style. The effect would be magical," he said.
With the combined weight of a Rothschild, a Sainsbury and Department of Culture support it seems the capital could soon have a new public river frontage, an art gallery extension adjoining it, and (when opposing interests are reconciled) a new concert venue in memorable surroundings.
It is in some ways the most exciting cultural development about to take place. Yet all the attention focused on more notorious arts lottery projects means it has barely received any public mention.
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