If there's a better lifelong-learning topic than wine, I've yet to hear about it.

It's a realm that's both wide and deep, affording opportunities to delve into geography, geology and especially history. It's a domain filled with fascinating people worthy of their own biographies, whether they be seventh-generation growers in Spain or self-taught vintners in Walla Walla.

And there's the wine, so much wine, so many grapes from so many places. It's great fun to check out relative obscurities such as assyrtikos from Santorini and tannats from Uruguay. But it's perhaps a better learning experience to figure out which renditions of the more available varieties you prefer. In general, that can be done continental-style: in side-by-side-by-side samplings of the same varietal from different land masses, preferably in the same price range.

Yes, geography matters. On our shores, California is a beacon of sunshine and, as a result, fruit ripeness. Meanwhile, most European countries have cooler climates, shorter growing seasons and often a good bit less sunshine during those seasons. Which means less sugar/lower alcohol (again, in general) and more of a balance between fruit and acidity.

These sampling endeavors will be entertaining as well as edifying, as they entail convening with friends to scope out a variety of wines of similar types. I have selected readily available wines that not only are exemplars of their grape and place but also won't break the bank, falling almost invariably in the $10 to $15 range. These are all bottles that I've enjoyed thoroughly over the years.

Sauvignon blanc: Giesen is the epitome of New Zealand sauv blanc, with soaring grapefruit notes and a racy texture. Ditto Pomelo as a paradigm for California: ripe fruit, super-smooth from start to finish. Domaine du Rin du Bois Touraine carries the flag proudly for France's Loire region, with lively flavors and lovely fruit/mineral/acid harmony.

Chardonnay: There's less geographic diversity here because a more important distinction is between the buttery, oaky style (which has been toned down in recent years) and the purity of unoaked chards. I've been enjoying the J. Lohr Arroyo Seco Riverstone for decades; it's plush, rich and spicy on the nose and palate. Four Vines "Naked" is just as lush on the nose and fruit-packed on the palate but with a crisper finish. The Les Chenevieres Mâcon-Villages combines Old World restraint and slate with polished fruit flavors.

Pinot gris/grigio: "Gris" is French and made mostly in Alsace, with the Hugel Gentil's Alpine-flower aromas and green-apple notes representing it deftly. "Grigio" is Italian, and the lemon-lime-y Cantina Tramin Sudtirol beautifully transforms from bracing beginning to silky finish. Oregon generally goes with "gris"; Benton Lane is a bright, zesty delight with late-breaking oomph. Estancia, like most of its California peers, uses "grigio"; it's tropical through and through, evoking the spices and the fruit of warmer climes.

Cabernet sauvignon: Currant and plum (along with vanilla from the oak) are hallmarks of California cabs, and the McManis provides them in spades. Washington offerings tend to add more herbal aspects and red fruit, and Exhibit A comes from Boomtown (which is closer to $20 but still a stellar bargain). Maybe it's psychological, but Chilean cabs such as the Casas del Bosque Reserva almost always seem to include hints of coffee, plus acidity. Bordeaux reds, on the other hand, tend to be dusty, more balanced and lower in alcohol; Chateau L'Orangerie Superieur hits all those check marks.

Syrah: The contrasts get stronger here. Most French versions are blends, and the spendier ones tend to be large and in charge. The Hecht & Bannier Languedoc Rouge, though, is a classic French table wine, juicy and peppery/herby and again more drinkable because of lower alcohol levels. Cycles Gladiator, like McManis a superb producer of an array of value wines, almost screams "California" with its plump, generous fruit and supple finish. Aussies label this grape Shiraz; the Yalumba "Patchwork" Barossa is über-ripe and super-soft.

Pinot noir: Here's a grape with a national and international dichotomy (and higher prices than the earlier wines mentioned here). The exception is Parducci Small Lot Blend Mendocino, which is generous, chuggable and the rare pinot that pairs well with grilled food. Contrasting such California cherry-cola pinots are Oregon's bing-cherry efforts, such as the lean and clean Fullerton "Three Otters." Darker cherry/berry elements typify pinots from New Zealand, but wines such as the Sileni Hawkes Bay still have silky finishes.

And while it's exceedingly difficult to find good pinot noir from Burgundy for less than $30, the Bouchard Pere et Fils Bourgogne in the $20 to $25 range is a good effort for the price: alluring nose, refined red-fruit flavors, silky finish.

It would be surprising if everyone at your tasting agrees within a category. But here's another great thing about wine that comes into play here: There is no "wrong" choice for one and/or all.

Bill Ward writes at decant-this.com. Follow him on Twitter: @billward4.