Tesla fans flocked to the carmaker's new factory near Berlin on Saturday, where Chief Executive Elon Musk staged a county-fair style festival to celebrate the site's imminent opening.
Musk hopes in coming weeks to get the green light to start production at the site, which at its peak will produce 500,000 battery-electric vehicles (BEVs) a year - more than double Germany's BEV production in 2020.
While Tesla has said the site will bring Germany significantly closer to achieving its e-mobility goals, some locals and environmental groups are unhappy with Musk's approach which they say flies in the face of German business culture.
"I would tell him to stop building electrocars but rather fly to Mars," said Manu Hoyer, who led a small protest of locals who oppose the project on environmental grounds, saying it will pollute drinking water.
Tesla has also submitted plans to invest 5 billion euros ($5.8 billion) in a battery plant with 50 GWh capacity next to the site, outstripping Volkswagen's planned 40GWh capacity site in Salzgitter.
It offered 9,000 tickets to the festival, with locals from Brandenburg state given priority.
"Giga Berlin-Brandenburg fun party today!" Musk tweeted in German shortly after the event started, and then joked with a Twitter follower who replied to correct his German.
Musk is expected to make an appearance at the event for which the site was transformed for the day with sprawling music stages, booming speakers and a Ferris wheel.
"Look, Mummy! A Tesla," shouted an excited nine-year old Emil, who was one of many children standing in line with parents waiting for a 90-minute site tour. "This day is unique," said self-proclaimed Tesla fan Fred Schroeder. "The Tesla factory in Germany will be opened to the public for the first time. That is a very special day."
The latest consultation on public concerns towards the site closes on October 14, after which the environmental ministry will decide whether to reject or approve it.
Brandenburg's economy minister has pinned the chances of approval at 95%.