It was 175 years ago that California officially became a state, and there's a free block-long festival on Tuesday to mark the occasion.

The celebration will include a laser light show on Capitol Mall, along with music and free cake. The block party marks Admission Day, when California officially became a state in 1850.

Peter Burnett, California's first governor, made the announcement back then.

"The governor officially made a welcome speech to all Californians, sort of an inaugural speech for the state, and that's when they really joined the United States," said Armando Quintero, director of California State Parks and Recreation.

The population of the Sacramento region was already dramatically growing at the time, thanks to the discovery of gold two years earlier.

"It was extraordinary wealth relative to the rest of the nation at the time," Quintero said.

California's first state capitol was in San Jose, not Sacramento, and it didn't move here until four years later. A lot has changed since those early days.

"There are a number of firsts that have taken place in California: discoveries, inventions, the first hydroplant in the entire world was right up here just below Folsom," Quintero said.

So it's only fitting that this demisemiseptcentennial celebration features some state-of-the-art technology invented in the Sacramento region, like the laser space cannons that will be part of the party. 

There are 31 of them to mark California being the 31st state.

"We will manipulate the color, fade down, fade up, change things and it's really a beautiful thing to see," said Tim Anderson, owner of Nu-Salt Laser International.

"This is coherent light," said Ben Davis, CEO of Illuminate. "It behaves differently than regular light in every single way, so I think we're going to touch on some moments of magic and unexpected joy."

The family-friendly celebration is a chance to highlight California's history and the things that make this state so unique.

"175 years of being one of the most diverse states in the nation," Quintero said. "Natural areas, historical areas, coastline, mountains, deserts, and it's all California, and it's where you live."

The event runs from 6 p.m. to 9 p.m. and will be held in front of the Capitol on 10 Street, which will be closed off to traffic beginning at 6 a.m. to accommodate the crowds.