The opening came after years of preparation. It's our state's own "Smithsonian" - a museum that seeks to create a new wave of Pacific Northwest history buffs.
"You can come out and do something fun that is hopefully a little bit educational," said Kathleen Schwegel, who came out for Saturday's ribbon cutting.
Mayor Mike McGinn did the honors - with some help from the next generation.
Inside the museum, each wall is decked in historic Seattle artifacts.
"We have some of the great icons of Seattle's history, including Boeing's first-ever commercial airplane," says MOHAI's executive director, Leonard Garfield. "We've got the first sign of Starbucks. We've got that famous Rainier 'R' we used to see on I-5."
The museum moved into the Naval Reserve Armory after outgrowing its old location just off of Highway 520.
Suzanne Estey, who attended the opening ceremony, says, "I went to the old MOHAI as a kid quite a bit, and we're just really excited to see the next lifespan of a museum that tells the history of our region."
The museum's new home has 50,000 square feet of interior space that will be used to display nearly 4 million artifacts - the past kept alive to help carry us into the future.
"When you live in a place like this that has a lot of history, it's something that connects you to the place - and that's what I want to do for my kids," Schwegel said.