Barricades were set up last night around the Hyatt Regency, organizers are excited Donald Trump is kicking off the convention. But if it's anything like Southern California's events, it could be a wild weekend.
About 20 people were arrested by Costa Mesa police last night as Trump protesters and supporters took to the streets outside a venue where the Republican presidential candidate was speaking.
WATCH VIDEO: Car does donuts around Donald Trump protesters
In Burlingame, police have spent a month planning and asked for help from every agency in the county and also state and federal officials.
Donald Trump will speak at the opening lunch; John Kasich speaks tonight and Ted Cruz tomorrow followed by his new running mate Carly Fiorina. People are coming from all across the state to be at the convention.
RELATED: Upcoming GOP Convention already met with protest
"A lot of times in the past the nominees had already been decided by the time we got here so this is a great opportunity to really engage. We've got three candidates to choose from and a lot of our republicans. Our Republicans in the state are excited to make that decision in June," said Kaitlyn MacGregor, Communications Director California GOP.
Trump and Cruz's events are already sold out. Trump is expected to speak at 12:45 p.m.
Click here full coverage of the 2016 election.