(GUARDIAN) — It is the most valuable and fascinating drinks cabinet in the world. In a locked and chilled store room in what was once a cowshed, Bay van der Bunt pulls a dusty bottle from the very end of a wooden shelf filled with similarly dusty bottles. He pours the merest sliver of clear dark-amber liquid into a glass.

“That’s about seven sips. Don’t drink it. Don’t swallow. Take a tiny sip and leave it in your mouth,” he instructs.

The 203-year-old brandy tastes smooth and warm and hard not to swallow. But a bottle 50 years younger than this sold for €119,162 (£100,000) at auction last year, so it seems only right to savour every sip, especially if each one is worth around €260. “That’s probably the oldest brandy you’ll every taste,” says Van der Bunt, tactfully omitting “and the most expensive”.

Some people have walk-in wardrobes; Van der Bunt, 63, has a walk-in drinks cupboard, filled with some 5,000 bottles of old spirits and liqueurs: cognac, armagnac, port, chartreuse. It has taken the Dutchman nearly 40 years to build up what is believed to be the largest such private collection in the world, and now he is selling it lock, stock and dusty bottle for €6m (£5m) or near offer.

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