Many of the teams are unpacking their gear, while other riders were hoping to get some last-minute training in.
"We just go out for a small ride, an easy one. Yesterday we had a long flight in," Kjell Carlström said.
Getting expensive bicycles ready for Saturday is a careful ritual -- the bikes cost between $8,000 and $10,000 apiece.
The race could draw 75,000 people to downtown Sacramento alone.
"The fans, that is the biggest thing here in my opinion. To race in front of a big audience or a big crowd, that is nice," Carlstrom said.
The cyclists head to the Bay Area for the next several legs of the race. After that the riders head south.
The star of the race is Armstrong.
Armstrong retired from competitive cycling after winning his seventh Tour de France in 2005. In September, he announced he was coming out of retirement and reuniting with general manager Johan Bruyneel, his team director during all of his Tour de France victories.
Last month, Armstrong finished 29th in his comeback debut race at the Tour Down Under in Adelaide, Australia.
His star power has given the sport of cycling a much-needed boost, said Levi Leipheimer, the two-time defending Tour of California champion and Armstrong's teammate.
"It certainly gained a lot of media attention. Lance has gained a lot of media attention, and that's all positive," Leipheimer said. "I think he's increased the pie of cycling media, not necessarily taking anything away from anyone or another team."
Leipheimer said Armstrong or not, he still considers himself to be the clear favorite in this year's race.
But he said Armstrong can "be a factor" in the race.
"I think he's already shown that in the Tour Down Under. He was strong. He was in the mix," Leipheimer said. "Whether he's at his best, I doubt it. I think he's still going to improve, but that's normal. In his head he's thinking that way as well. He's using these races to get back into it."