Most activities will take place at Moscone Center from Aug. 28-30, with the championship finals scheduled for Sunday at Chase Center.
As the city prepares for the influx of visitors, Pokémon fans are already gathering, trading collectibles and building anticipation for one of the franchise's biggest annual events.
"We're figuring out what to trade right now," said one fan.
"I've been collecting for 8 years so I've accumulate quite a bit," said a fan at Pokémon meetup Friday night.
Some say the event's international reach is a major part of its appeal.
"It's a big deal," said Trey Holt of Austin, Texas.
"This is pretty international. People are flying in from all over," Holt said.
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The Moscone Center is undergoing preparations for both the Pokémon World Championships, commonly known as "The Worlds," and the new fan convention, Pokémon XP.
Dave Tran, a dedicated player, said he has been looking forward to the event coming to the city.
"Super excited. Finally coming to SF which is great," Tran said.
For many attendees, the gathering offers an opportunity to connect with fellow fans.
"It's basically like a huge gathering," said Katherine Davey.
Davey said she is particularly excited about Pokémon XP, which will feature activities beyond competitive play.
"It's the first time to have a get-together with everyone. They'll have all these little booths," she said.
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Organizers say attendees can expect scavenger hunts, panel discussions, trading opportunities for cards and pins, and other fan-focused activities.
"It's my favorite Pokémon and I basically want to hand these out," Davey said while showing Pokémon-themed items.
While Moscone Center will host most of the events, the championship finals will be held at Chase Center on Aug. 30.
Hotels across the city are preparing for the large crowds.
"We will be completely sold out with Pokémon attendees," said Christina Rea, director of sales and marketing for the W San Francisco.
"A lot of the attendees are coming in next Friday," Rea said. "There's going to be 50,000 attendees from all over the world coming in so a truly international showcase for San Francisco."
Fans say the championships and convention will be a major attraction both for the Pokémon community and for the city itself.
"Woah! Going to be awesome--especially for the city," Tran said.
With thousands of visitors expected and venues across San Francisco preparing for packed crowds, the Pokémon World Championships and Pokémon XP convention are set to become one of the city's largest fan gatherings of the year.