More on the potential for underwater ageing, which seems highly likely to be nonsense, from Decanter:
Dark? Check. Cold? Yes, very. Constant conditions? Definitely. Potential for slow oxygen ingress? None.
Through the cold and murk I spy a giant and presumably rather expensive PR stunt!
Jim
I’m pretty certain this has been tried dozens of times before, and yes it is probably a gimmick we will all end up paying for!
On a related note, Jean Marc Laffitte (of Madiran) had a project where he was ageing some wines in the caves at Lourdes, presumably to have a wine counterpart to holy water? It all seems to have gone quiet on that front, probably soon to emerge as an expensive trinket sometime soon… 
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