50 Post Office Square is a 782,000-square-foot, 20-story building that is known for its art design. It’s in a prime location, bordered by Franklin, Pearl and Congress Streets. The property, formerly known as 185 Franklin Street, was completed in 1947. Architects worked with the owners to reposition the building as a Class-A Office building, re-configuring the ground floor to add retail and a new contemporary lobby.