PORTLAND, Ore. -- The Fifth Avenue Building reopened Wednesday morning, more than a week after it first closed due to concerns about a collapse. Sidewalks around the building were also open again.

Background: Downtown Portland building evacuated

Cinty Forte was one of the first people to go back inside. She was on the fourth floor, Tuesday, April 11th, moments before the big evacuation, and she heard a loud sound. “I didn't think anything of it. I thought they were doing construction, and they came in yelling to evacuate, so we evacuated.”

Forte says she’s a bit nervous to go back inside the building, even though engineers say that it’s safe to do so.

“It’s scary,” she said. “I have to trust they know what they were doing.”

KinderCare day care remained closed Wednesday morning. But 24 Hour Fitness did reopen, according to an employee.

Photos: Building evacuated after threat of collapse

“I think the danger was parts of the building falling off on people, and I think they've mitigated that for the most part,” said gym member Chris. “I’ve had to drive all the way to the Pearl, that's out of my way. This location is a lot more convenient.”

Engineers still don’t know what caused the façade to buckle. It’s still under investigation.

“We are currently having a contractor stabilize the exterior façade tiles that collapsed and then they will be able to remove them in order to see what caused the buckle,” said Kelley Duncan Brewster, Vice President of Operations for Melvin Mark Companies.