(AP) Maine’s oldest and largest public library system is reopening to the public.

The Portland Public Library said the main library in Monument Square will open on June 22. Two levels of the building will be open with reduced hours. Hours will then expand in the first week of July, the library system said.

The Peaks Island brand of the system is scheduled to open on Tuesday. Two other branches, the Burbank and Riverton branches, are expected to announce opening dates and time soon, the system said.

The system said everyone entering the library will be required to wear a mask.

“We serve people from every age, demographic, and background, including young children, medically vulnerable individuals, and others who are not yet vaccinated. The mask requirement helps us protect those who may still be at risk from COVID-19,” said Sarah Campbell, the library executive director.

The library system said it’s also limiting visits to 30 minutes. It’s discontinuing its curbside to-go services as branches reopen.