It’s hard to imagine that upwards of $30 million in treasure could reside deep within the grim, fortress-like American Bank Note Company building that hulks over the east side of the Bruckner Expressway in the Hunts Point section of the South Bronx. No, that treasure isn’t a trove of the international currency, which, along with stock and bond certificates and stamps, was once printed here. It’s wine: more than 20,000 cases of the rarest and priciest glories of the vinous world, residing in a 150-foot-long, temperature- and humidity-controlled vault.

Those wines, which belong to private collectors, retail shops, and to clients of Christie’s, the largest global wine auctioneer, are in the care of a 4-year-old company called the Wine Cellarage. It maintains one of only a handful of large-scale facilities in the city that offer secure, climate-controlled wine storage space to the public (WineCare, Chelsea Wine & Storage, and New York Wine Storage Company are other such facilities). For the tiny minority of wines whose lifespan may exceed that of their owners, or even several owners, perpetual coddling is essential. “You’ll pay a high premium for bottles that can benefit from long aging,” the firm’s 40-year-old proprietor, Lars Neubohn, said in a recent interview at the facility. “Leaving aside the disaster scenario, in which overheating kills fine wines on the spot, you’re just hastening the chemical reactions that lead to premature aging if you don’t store them properly.”

The perfect beauty sleep for wine occurs at a constant temperature of 55 degrees and “a baseline of 60% humidity.”

Mr. Neubohn’s first career, after business school at the University of Washington, was in financial services. Then, after an Internet start-up he’d been working for folded in 2002, “I wanted to do wine, but not just by opening a wine shop,” he said. “I’d worked in the self-storage business, where I’d crunched a lot of numbers, and I knew that they could be compelling if you could fill up your space.” At least as compelling is the need for wine storage space in the city, where even spacious apartments may not be suited to the needs of storing a significant collection. “Posing as a customer, I realized that the storage market was at capacity,” he said. Wine Cellarage’s first home, opened in 2003, was a cellar in the Red Hook section of Brooklyn. Its sole employee, at first, was Mr. Neubohn. “Working for three start-ups, I’d seen many millions of dollars just go up in smoke, and I was determined not to go that route,” he said. “So it was just me in the beginning. I drove the truck myself. Calls to the office would be forwarded to my cell phone while I was driving.”

Thanks to a customer base made up largely of Wall Streeters who bought more expensive wine than they could ever drink, Wine Cellarage ran out of space in Red Hook after just one year. “The Bronx was the last frontier in terms of affordable space, and I’d see that huge building every time I drove north on the Bruckner,” Mr. Neubohn said. Following the departure of American Bank Note in 1985, that building had a bounty of strong-walled space to offer. Wine Cellarage moved into “the belly of the beast” in late 2005 after outfitting a 10,000-square-foot main storage space with what Mr. Neubohn calls “freezer box insulation” and custom-designed climate-control equipment.

Late in 2006, Mr. Neubohn signed up Christie’s, the world’s largest wine auctioneer, to take more than half of the storage facility. Previously, Christie’s had stored wine consignments outside the city, as all the other local wine auctioneers still do. Wine Cellarage, on the other hand, is only a 30-minute trip by subway from Christie’s Rockefeller Center quarters. Christie’s keeps a full-time cellar man on premises to inspect incoming consignments, organize them, and ship lots to winning bidders. Currently, they include about 1,000 cases of trophy wines to be auctioned in March. Private clients pay about $25 per case annually for storage. “A funny thing about this business is that it’s turned out to be only part storage,” Mr. Neubohn said. “We do lots of shipping logistics, moving wine all over the world.” Last August, for example, he moved a $2.3 million wine collection to a London home.

Normally, fine wine is not shipped in hot weather, but this client didn’t want to wait for autumn. “We packed it all in containers lined with dry ice for the flight over,” Mr. Neubohn said. For Christie’s inaugural sale of spirits (formerly banned from auction sale in New York) last month, he arranged the transport of a large consignment of rare whiskey that traveled to the Bronx via refrigerated truck from Bellingham, Wash. “One of our advantages is that we’re at the confluence of excellent toll-free roads, including the Bruckner and the Cross Bronx expressways, and we can back up a 53-foot trailer to our loading dock,” he said.

Visitors are normally prohibited from entering the main wine vault, but Mr. Neubohn agreed to give this reporter a tour. Passing seemingly endless rows of steel shelving laden with wine cases bearing winedom’s great names and storied vintages, a wine lover’s heart is quickened. There was a case of the legendary Mouton Rothschild 1945, for example, each bottle resting in the original straw bed. A case of six magnums of that wine holds the auction price record for Bordeaux, set at Christie’s in 2006: $345,000. And in a nondescript cardboard box, swathed in foam wrapping, lay a single double-magnum (equal to four regular bottles) of the even more legendary Château Lafite Rothschild 1865, sold at Christie’s last October for $72,000. After 142 years, this wine is reputed to be splendidly alive and awaiting its ultimate dinner.

Those bottles, and many more wine gems, now reside in what was once American Bank Note’s storage room for etching plates used to print money. It’s unlikely that many of those currencies are still in circulation. But the best wine lives on here, reaching ever great values.