SEATTLE -- Plan to catch the fireworks on the Fourth? You'd better head out early.

Organizers of the fireworks show at Gas Works Park urge people to arrive early and to leave cars at home as tens of thousands are expected to attend the celebration.

Biking is a terrific alternative to driving, say the organizers, who have provided a list of bicycle routes from the surrounding areas. An express access bicycle entrance will be set up on the northwest side of Gas Works Park.

Spectators can also take a Metro bus, but organizers believe the crowd will overwhelm the available buses after the show.

Another option is to drive downtown, then take the Seattle Streetcar to Lake Union.

The fireworks show will kick off at 10 p.m., but family activities at the park will kick off at noon.

On Friday crews were packing fireworks in columns in preparation for the spectacular show.

"It’s, without a doubt, one of the most beautiful places to do a fireworks show in the United States," said Eric Tucker of Pyro Spectaculars, the show's designer.

The event draws a big crowd every year, but organizers expect to see an even bigger crowd of some 50,000 spectators this year as the city's only fireworks show.

So what happens if Gas Works Park fills up beyond capacity?

"Well, Seattle police plan on funneling them up the Wallingford steps...to north 40th Street, where they’ll still be able to see the fireworks," Tucker said.

Wallingford resident Charles Nelson knows what's coming, and plans to skip town.

"It’s just going to be a mob scene," he said on Friday afternoon. "I’m leaving in about 15 minutes, when the getting is good."

Some residents who live near Lake Union are concerned spectators will ignore the "no parking" signs posted around the neighborhood.

"I suspect it’s going to be pretty chaotic," said Cheryl Hubbell, who plans to avoid the big crowds around Lake Union. "We’ll stay in the city. We’ll enjoy it from one of the hilltops."