There are 225 hours of Oktoberfest, the suds-soaked Bavarian celebration that opened on Saturday. For 222 of those hours, there is beer.

The other three hours — the first three — have only cola, pretzels and card games. And an air of nervous anticipation that recalls Christmas Eve, if Santa Claus exclusively brought malt beverages.

Thousands of visitors will descend on Munich for the 190th iteration of Oktoberfest, which ends Oct. 5. Only a small set of hard-core enthusiasts will experience the joy and agony of the wait for its main attraction.

“It’s a little bit strange now,” Sibille Bauer, 32, a server at the Hacker-Pschorr brewery tent said on Saturday morning. It was just past 10 a.m., and she was surveying a pavilion packed shoulder-to-shoulder with men in leather pants and women in traditional Bavarian dresses, none of whom were imbibing.

In two hours, Ms. Bauer said, she would be carrying fistfuls of steins to the orange, wood tables that surround the bandstand in the middle of the tent, depositing liters of amber “festbiers” for about $18 a glass. At the moment, she was mostly shooing away latecomers, who were begging for a highly-coveted table seat.

But, she said with a smile, “after 12 o’clock, the beer is coming.”

The gates to the festival grounds open at 9 a.m. on weekends, including the traditional Saturday start. The mayor of Munich does not tap the ceremonial first keg until noon, after which servers begin dispensing alcoholic beer.

It is nearly impossible for most visitors to secure a reservation in the festival’s hallowed beer tents, where the main events of Oktoberfest play out with a brass-band soundtrack. But many seats are first-come, first-served, and so people race to grab one in the first moments after the gates open — usually after camping out overnight to snag a good spot in line.

That means that the crowd in the tents from 9 a.m. to noon on Saturday is a bubbling concoction of excitement and fatigue, fueled by energy drinks and impatient for alcohol.

They pass the time playing card games like Uno or Kniffel, a sort of German version of Yahtzee, at their tables. They buy oversized pretzels or lapel pins from vendors walking the now-empty aisles. They catch up with friends, and they make new ones.

Laura Melz, 31, of Cologne, Germany, was sitting in the tent of the historic Hacker-Pschorr brand of beer a little before 10 a.m. A friend was braiding her hair, which had fallen loose in her run from the security line. Ms. Melz was sweating and feeling lucky. She had found a trio of Canadians in the tent who invited her group to sit next to them.

Ms. Melz was smiling, perhaps from the adrenaline and from the Prosecco her friends had shared in line before their run. Once the beer started, she said, they would sing together, dance on the tables and, naturally, drink.

“We are not too sober,” at the moment, she allowed. “But at 12, we will be sober” — briefly, at least.

Nearby, in the Schottenhammel tent, popular with young Germans, Anton Frank was relaxing with 30 friends, spread across three tables. Mr. Frank, 18, is from Munich, though he is doing an internship this fall in Austria. He said he expected to drink somewhere between three and five liters of beer after noon, perhaps followed by some bubbly or other wine. Last year, he attended Oktoberfest for 14 of its 16 days, usually after classes ended, topping out at eight liters of beer (that’s four of the large soda bottles at an American grocery store) in a single visit.

“I’ll never do that again,” he said. “It’s expensive.”

Giorgi Mtchedlishvili, another 18-year-old from Munich, was drinking colas and playing cards at a table on the other side of the tent. He secured an early spot near the front of the security line, then allowed some other young attendees to cut in front of him, for a price. He said he made 300 euros.

“I’ll buy a round for my friends,” he said.

Outside, a parade of horses snaked through the grounds, carrying barrels of beer. Just after 11, the Schottenhammel crowd broke into claps and stomps as the parade arrived. Just before noon, the mayor, Dieter Reiter, stepped to the keg, brandished a brass faucet and tapped it in with a wooden mallet.

Just after 3 p.m., I texted Mr. Mtchedlishvili to ask if he was having fun.

“I am 3 beers in,” he replied.