Architectural drawings were also presented at the well-attended meeting Thursday.
"These are not final designs," Healy said during the presentation. "These are only conceptual."
One proposed site is directly across the street from City Hall, where the Cambridge post office and a branch of the YMCA currently reside.
The others are located in Central Square, at 65 Prospect Street near Central Square and at the site of the current main library on Broadway next to Cambridge Rindge and Latin School.
"Those are the sites we have the most information on," said Councillor Marjorie C. Decker after yesterday's meeting.
Decker said the council hopes the decision will be made soon.
"We all want to get this done by the end of the spring," Decker said. "That's our commitment."