Oktoberfest opened in Munich on Saturday under heightened security, with backpacks banned and a fence erected around the beer festival's grounds to ensure that all visitors are screened.
The new controls come as Germany remains on high alert since two Islamic State-claimed attacks in July, although Munich's police chief says authorities know of no specific threat against the event.
The security checks and rainy weather didn't dampen the crowd's spirits, with visitors dressed in traditional Bavarian clothes queueing long before the first beer tents opened at 9 am (0700 GMT).
The two-week festival that is expected to attract 6 million people officially kicked off when Munich Mayor Dieter Reiter tapped the first keg of beer at 12 pm.
"Ozapft is!" exclaimed Dieter, the traditional Bavarian exhortation to begin the celebrations. The phrase loosely translates to "it's tapped."
This year's Oktoberfest is the 183rd since it began in 1810 as a horse race held on the occasion of a Bavarian royal wedding. There have been some lapses due to war and cholera epidemics.
Some 450 security personnel will be deployed during peak hours to conduct checks on the incoming revelers.
The backpack ban includes all bags that can carry more than 3 litres of liquid. The new fence is mobile, with its nine separate units able to be dismantled within 50 seconds so that visitors can flee in emergency situations.
On July 24, a Syrian suicide bomber detonated an explosive device that he had been carrying in his rucksack outside a music festival venue in the Bavarian town of Ansbach, injuring more than a dozen. A week earlier several people were seriously injured in a knife attack on train near the city of Wuerzburg, also in Bavaria.