"It's really beautiful," said one visitor. "It's been a long time coming," said another, adding, "but I think it's well worth it."
RELATED: San Francisco's Salesforce Transit Center: By the numbers
Hours after the public open house began, there were still crowds.
The $2.26 billion transit center is impressive. One million square feet and four levels above ground, it will connect commuters with the Bay Area.
It's commute game changer for Lisa Howlett.
RELATED: OVER IT: Exclusive peek inside San Francisco's 'Grand Central Station of the West'
"I don't live super close to BART in Oakland, so there's a lot of transbay buses that go closer to my house, so I'll probably choose to use that now," Howlett said.
Folks grabbed photos on the center's cable-stayed bridge, which will allow transit buses to fly over downtown's notorious traffic.
"People are going to cross over six busy streets of traffic during congested hours, and they're never going to touch a city street," said Transbay Joint Powers Authority Spokesperson Christine Falvey.
RELATED: San Francisco's Transbay Terminal running out of funds for construction costs
The center's crown jewel might be the five-acre rooftop park, a place to hang out and take in views of the city's skyline.
"It's amazing," said Oakland resident Paul Stanis. "It's more than a transportation hub. It's a place where people can gather and it's been a great day so far."
The coolest feature might be the center's giant steel oculus -- a huge skylight that lets sunlight in four stories down.
The transit center took eight years to build and commuters endured a lot of traffic headaches during construction.
One visitor summed it up: "It's nice after so many years the construction is finally over."