In a battle of Canada Day events, it's Surrey versus Vancouver.

The big question is, whose July 1 bash is bigger?

Organizers of the celebration in Surrey say their yearly event, at Millennium Amphitheatre in Cloverdale, has grown to become "the largest Canada Day celebration in western Canada."

Meanwhile, in Vancouver, they're calling the harbourside party "Canada's largest birthday celebration outside of Ottawa."

Last year's Canada Day event in Surrey drew more than 100,000 people, while organizers of the event at Canada Place in Vancouver say an estimated 200,000 people showed up in 2011 for daytime events, plus 120,000 for an early-evening parade and a whopping 450,000 for a fireworks show.

On the face of it, Vancouver's event looks larger, but organizers of the event in Surrey question the numbers.

Mary Rukavina, manager of special events for the City of Surrey, says it's a matter of how attendance is calculated and exactly where the action happens.

"The big kicker for us is the geographical space," she told the Now. "We have 15 acres of event space, which is close to 6.5 hectares. Our event is all in one big place."

It's a different story in Vancouver, Rukavina said.

"From what I understand, they have different pieces of Vancouver celebrating Canada Day as part of that event, in different areas," she added.

"They have a stage at Jack Poole Plaza and then you have to go down the corridor, down the street, for another mini kind of celebration. It's all disjointed."

As for attendance, Rukavina says the event in Surrey has attracted up to 125,000 in a single year.

"I want to know where in the City of Vancouver do they have someone go through the site, in one place, and have the number hit 125,000 people," Rukavina said.

As for an estimated 450,000 people watching the Canada Day fireworks show in Vancouver, Rukavina added: "That must be a lot of people watching from condo balconies."

The Canada Day celebration in Vancouver is a single event that stretches from Canada Place west to Harbour Green Park, said Robyn McVicker, director of events with Canada Place.

"It's a very large footprint. It's all one event, not broken up. It's all connected," McVicker told the Now.

The number of viewers for the fireworks at Coal Harbour includes people from the North Shore.

Added McVicker: "We always hear Surrey saying they are the biggest Canada Day celebration in western Canada, and we know what our numbers are. I didn't know Surrey got the numbers we get. Canada Day at Canada Place gets upwards of 750,000 throughout the whole day."

The party Sunday in Cloverdale features musical headliner Sam Roberts Band, who performed for Prince William and Kate at Ottawa's big Canada Day event in 2011.

In Vancouver, Canada Place festivities include performances by Spirit of the West and Alex Cuba.

Locally, Canada Day celebrations Sunday also include flag-waving events at beaches in White Rock and at Chalmers Park in North Delta.

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