Jay Rosen's love of wine developed as a necessary provision during college. "I never liked beer, it upset my stomach," says Rosen, a wine cellar architect from Martinsville, N.J. "So in college one of my friends and I would just drink wine. There was this store nearby. We used to go explore, try this, try that." It wasn't anything special, he says; fine wine then appealed neither to his wallet nor his nascent palate.

Fifteen years down the road, his appreciation had deepened to the point that he wanted to buy some Bordeaux, starting with the 1990 vintage. It was a buyer's market. "I remember buying Latour for $65 a bottle at a place in Jersey," recalls Rosen, 60. "Literally, they had a stack of cases of Latour sitting on the floor." A bottle of '90 Château Montrose set him back $24; Cheval-Blanc, $67. In all, Rosen purchased 37 cases of 1990 Bordeaux, both as futures and on release. He thought the wines were fabulous, and started tasting more. He bought some 1982s, at the time still inexpensive by today's standards.

In need of a storage space for his growing treasure trove, Rosen, who then renovated houses for a living, would bring home a couple of two-by-fours every day and nail them into his basement walls. Plank by plank, he completed his 1,500-bottle cellar over a period of several months, also installing insulation and temperature controls. The construction of this makeshift cave compelled Rosen to start building wine-storage areas for clients, and he soon launched the cellar construction company he owns today, Washington Valley Cellars.

Within a couple years, Rosen remembers, "My wife was like, ‘You need to build yourself a real wine cellar. You know, if you're gonna do this for a living.' " So Rosen built his 4,000-bottle dream cellar adjacent to his dining room. Framing the space are limestone floors and a plaster-finished barrel ceiling. The wine racks are horizontal rather than vertical—a feature that's become a Washington Valley signature. "I think it looks a bit more elegant and refined that way," Rosen explains, citing the difficulty of sanding down the wooden pegs used in vertical shelving.

Rosen owns approximately 130 magnums and 35 bottles in even larger formats. These statement bottles are the cellar's focal point: Racks of 3-liter bottles rest below a slate counter, and a floor-to-ceiling cascading waterfall rack shows off Rosen's 15 magnums of 1982 Bordeaux. Why the fascination with large formats? Simple, says Rosen: "Because they look sharp."

Sharp, indeed—but it's not every day that you find an excuse to pop open, say, a 6-liter of Hubert Lignier Clos de la Roche 1999, signed by Hubert's son Romain, which Rosen counts as his favorite bottle. "You need a big shindig to open these big bottles," Rosen says. Every other winter, he and friends stage what has become known as the Big Bottle Extravaganza, to which each friend must bring a 3-liter or larger bottle. And Rosen's friends, many of whose wine cellars he has built, are no slouches. Past parties have involved a 6-liter of E. Guigal Hermitage 1995, an imperial of Château Pichon Longueville Lalande 1989, a 6-liter of Château Haut-Brion 1985 and an imperial of Château Cos-d'Estournel 1990.

Bordeaux was Rosen's first love, and so it remains. "In the mid-'90s, I liked Bordeaux a little better than California," he says. "It seemed like Bordeaux had a little more complexity to it, was more thought-provoking. California wines became kind of in-your-face and jammy." The exceptions were the chewy, brambly wines of Howell Mountain, for which he has a special affection.

Like the wines he cellars, Rosen's palate is evolving as time passes. He now finds fascination in the subtleties of vintage Champagne, aged Alsace Riesling and red Burgundy. This curiosity in new wine doesn't indicate that his buying will slow anytime soon. "Maybe it's not the best habit," Rosen says with a shrug. "5,000 bottles of wine!"

What's in Jay Rosen's Cellar?

Number of bottles: 5,000 (1,000 downstairs; 4,000 upstairs)

Verticals: E. Guigal La Mouline, Le Turque and La Landonne, 1990-2004, Domaine du Pégaü 1995-2010, Domaine Ferrando Châteauneuf-du-Pape Colombis 2007-2011 (3L), Clos de Tart 1985-2010 (5 bottles, 3L)

Methuselahs (6L): Hubert Lignier Clos de la Roche 1999, Château Cheval-Blanc 2005, Château Margaux 2005, Château Canon-La Gaffelière 2000, Château Troplong Mondot 2000

1982 Bordeaux: Châteaus Latour, Cheval-Blanc, Haut-Brion, La Mission Haut-Brion, Margaux, Mouton-Rothschild, Ducru-Beaucaillou, Léoville Poyferré, Certan de May, Bon Pasteur, Ausone, La Conseillante, Palmer (15 bottles in magnum)