Boston Mayor Marty Walsh announced Tuesday that on Feb. 1, the city will relax restrictions aimed at limiting the spread of COVID-19.

On that date, Boston will returning to phase III, step 1 of the state’s reopening plan, after reverting to phase II, step 2 before the winter holidays.

The move will allow several types of establishments — including museums, movie theaters, aquariums, and indoor fitness centers and recreational facilities — to resume operating, albeit at limited capacity, with 25 percent occupancy allowed.

“Throughout the pandemic, Boston and our public-health department have taken a cautious approach,” Walsh said. “We will only move forward with reopening if the public-health experts feel that it’s safe to do so.”

Right now, Walsh said, Boston’s COVID numbers are headed in the right direction. The positivity rate at the end of last week was 7.2 percent, down from 8.9 percent in early January.

“We’ve seen positive test rates go down in every neighborhood, which is a good sign, and we’re encouraged by seeing these numbers go down a bit,” Walsh said. “It’s still high — too high for where we want to be right now — but the numbers are definitely … going in the right direction a bit here.”

Still, Walsh said, Boston residents should continue to take steps like wearing masks and socially distancing to keep the virus from circulating.

Indoor and outdoor gatherings remain limited to 10 and 25 people, respectively.

The city also announced that the Strand Theater, in Dorchester, is serving as currently serving as a COVID-testing site, and that the Reggie Lewis Center, in Roxbury, will serve as a mass-vaccination site for eligible individuals during the first week in February. Fenway Park was previously announced as a mass-vaccination site.

“Local access is key, and we’ve continued to prioritize that along the way,” said Marty Martinez, Boston’s chief of health and human services.