(Mark Todd For The Washington Post)

It’s 3 a.m. on a Friday night in Toro, Spain, and somehow, I’ve been pulled behind the bar at Discoteca Q to mix cocktails for the group of regulars, who are still going strong. My rum Manhattans are a particular hit, as are my caipirinhas.

They’re such a hit that someone is now taking a photo of me with the owner, and I am told that this will appear in the local newspaper. Perhaps, someone suggests, I should move to Toro and join the staff, writing about cocktails in Spanish. I am seriously considering it.

My new friend Nicola tells me that Toro — which gives its name to the wine region in Castilla y Leon — boasts 100 bars for a tiny population of 10,000. If you are doing the math, that is one bar for every 100 people (including children). Back in the States, I live in a town with roughly the same population, and this is the number of bars we have: zero.

My job as a spirits writer often takes me out into the bright night life of big cities and into the many fancy bars and cocktail palaces that such metropolises offer. That is all fine and dandy, but at heart, I’m not such a big-city person. I’m more than happy to spend my time in some third- or fourth-tier, modestly populated provincial city. Or an even smaller and less consequential town or hamlet. I have only one stipulation: It must have a handful of good bars.

Yes, bars. There’s no other way to put it: I love bars. I judge villages, nations and continents by the quality of their bars. And there can’t be just one. A good bar town has a critical mass, offering a choice of drinking options depending on what mood one might be in on a particular afternoon or evening — or morning, as the case may be. There’s nothing better while traveling than the first drink of the day, taken at a cool bar on a hot afternoon. Place that bar in some provincial city where little English is spoken and give me a barman who takes his job seriously (but not too seriously), and I might be close to true happiness.

That is why I love Spain. It supposedly has the highest number of bars per capita in the world. Cities like Madrid and Barcelona and San Sebastian and Seville all boast amazing bar scenes and are rightfully praised for their tapas and pintxos. But it’s the per capita part of Spain’s bar culture that intrigues me most. You can literally find a great bar anywhere, not just in the tourist spots.

On my most recent trip, I was visiting several wine regions in Castilla y Leon, so I decided to drive north and stop in some of the less well-known provincial cities along the way: Valladolid (pop. 316,000), Leon (135,000) and up north into the Asturias region, to the coastal town of Gijon (264,000), before heading to Toro (10,000).

Since Valladolid is located within three winemaking regions — Rueda, Cigales and Ribera del Duero — it seemed the perfect spot in which to kick off my imbibing tour, and I appropriately arrived in town following an afternoon of tasting big red wines in Ribera del Duero. Because it’s also a university town, the bars are buzzing with people until late into the night. But the main reason I put Valladolid on the itinerary is because it’s the home of Los Zagales, which often wins the award at Madrid Fusion, the international chefs’ congress, for best tapas in Spain.

Long ago, Valladolid was a major city. In the late 15th and early 16th centuries, when Spain ruled the world, the monarchs made it the seat of imperial power on the Iberian peninsula. Christopher Columbus, who frequented the court looking for cash to fund his explorations, died here in 1506.

By the end of the 16th century, however, Philip II had moved the capital down to Madrid, and Valladolid drifted into simply being a pleasant provincial capital. It took only four centuries for it to re-emerge, in large part due to the cheap Ryanair flights that connect it to London, Milan and Brussels.

After napping from my wine-soaked afternoon, I joined my friend Marion at about 10 p.m. for the evening bar crawl. On a weeknight at home, this would be unthinkable, but Spain being Spain (where people sit down to dinner at 11), fellow bar crawlers were just beginning to filter into the bars. It’s a personal rule to begin every night in Spain with rose wine — something I rarely do at home — so we ordered Cigales and jamon iberico at a tavern near the Plaza de Marti y Manso called Vinotinto.

From there, I continued to El Corcho and Bar Zamora, which by 11 p.m. were packed with young people, and then toward the brightly lit Plaza Mayor and Calle de Pasion. There, I sucked down mussels from La Mejillonera and washed them down with beer served in small glasses. Beer poured into small glasses is another nice touch that I love about Spanish bars. Unlike the case when it’s served in heavy pint glasses, beer served in a small glass never gets warm. And it costs about a euro, or roughly $1.50. Why don’t more bars at home try this? Don’t worry, you can still drink as much as you want. The attentive bartender is always glad to pour you a second, and a third, and a fourth. . . .

Finally, continuing down Calle de Pasion, I finished up at Los Zagales, where the tapas certainly lived up to their billing. I figured I’d end the day the way I started, with Ribera wine. I ordered skewers of tomatillo-wrapped shrimp and bacon accompanied by lemon juice charged with liquid nitrogen, which fogged aromatically in that special molecular-gastronomical way.

The most delicious tapa of the evening was the last: black potatoes, fried and covered in squid ink, sitting atop a poached egg, cream of mushroom sauce and truffled pastry crust, served in a bright white clay pot. However, the name of this dish on the menu, “Obama in Casa Blanca,” was a little. . . I mean, seriously?

The following day, after another morning of Ribera del Duero, I drove farther north, to Leon. Just so that I wouldn’t feel like a complete lush, I toured the city’s 13th-century cathedral, one of Spain’s finest and considered a Gothic masterpiece, gorgeously illuminated in the evening.

After a half-hour or so of religious art and flying buttresses, it was time to visit Leon’s other major attraction, Barrio Humedo, or the “wet neighborhood” — a quarter of narrow streets and tiny plazas famous for the ridiculous number of bars in it. Locals claim that Leon has the highest number of bars per capita in Spain. Who knows whether it’s true, but I can say that I’ve never seen a square mile with as many bars as the Barrio Humedo.

Beyond the sheer number, what’s particularly noteworthy about the bars in Barrio Humedo is that, unlike the case in many cities, the tapas are free. You order a drink, you get a little plate of the house specialty. At La Parrilla del Humedo, I started with a glass of the local Prieto Picudo rose and a free plate of morcilla de Leon (the local blood sausage). At El Llar, I drank a fresh young red with garlicky potatoes and aioli. At Rebote, a great down-and-dirty pub where you just toss your napkins on the floor, I had great croquetas, which the bartender served atop each glass of beer.

Like Valladolid, Leon is full of students, some of whom invited me into a party at an Irish pub called Molly Malone’s, where we drank gin and tonics.

Now please understand, these were not just any gin and tonics. In Spain, they do not just shoot tonic water from a soda gun into a glass with bottom-shelf gin and toss in a pathetic lime wedge. In a town like Leon, most bars have at least a dozen or more excellent gins behind the bar, all to be matched with different brands of tonics, freshly poured from the bottle and served with large chunks of ice. Sometimes they’re garnished with lime, but often they’re garnished with other muddled citrus, or grapes or berries, and they’re often spritzed with an essence of spices or herbs.

The gin and tonic may have been invented by the British, and certainly it has gained wide popularity among Americans. But the Spanish have elevated the drink to almost an art form.

The next day — after an unsurprisingly late start — I drove a couple more hours north, into Asturias, to Gijon. As I ascended into the mountains, cruising through long tunnels, the whole landscape and climate changed. Where Castilla y Leon had been arid, hot and sunny, Asturias was verdant, cool and overcast. It was not surprising to learn that Asturias has a Celtic heritage that predates the Romans.

Gijon is a working port city, and the ancient Cimadevilla neighborhood, at the port’s headland, is wonderfully picturesque and full of atmosphere, especially at night when the sidrerias (cider houses) like La Galana or Casa Zabala begin to fill up.

Asturias is all about cider — or “sidra” in Spanish. Asturians drink about 100 liters (roughly 26 gallons) of their beloved sidra per person annually. “You will never see a region anywhere else where people drink so much cider,” said Jose Luis Roza, the commercial director at Trabanco, the cider producer I visited near Gijon. “The Spanish economy is terrible, but the cider houses in Asturias are full.”

In Asturias, you order sidra by the liter bottle. “You cannot order a glass of cider,” said Jose Luis. With tremendous dexterity, bartenders or waiters will pour out the cider in a long stream, holding the bottle high over their heads and splashing a little bit down into a glass held at waist level; this is to release the carbonic gas. You are served a couple of fingers of the agitated, cloudy cider, which you are then expected to drink in one gulp.

Sidra drinking is serious session drinking, and I was simply blown away by the staggering amount of cider that people in Gijon consume. For instance, at Sidreria Principado — where I paired my cider with amazing sardines drizzled with balsamic vinegar — I stood next to a middle-aged couple who casually tossed back three liter-size bottles in about a half-hour.

“Asturians are Celtic, similar to the Irish,” Jose Luis said. “But when it comes to drinking, we consider the Irish juniors.”

A few days — and several late nights — later, I’ve traveled back down south from Asturias to Toro. I’m finishing up my bartending shift and it’s nearing sunrise.

“Wow,” I say to Nicola, as the party begins to break up. “This is a pretty good bar town.”

“It’s Spain,” she says with a shrug. “Every town is a good bar town.”

Wilson, the spirits columnist for The Post’s Food section, is the author of “Boozehound: On the Trail of the Rare, the Obscure, and the Overrated in Spirits” (Ten Speed, 2010). Follow him on Twitter: twitter.com/booze