The Site 3 (238 Main Street) building combines new and existing structures, reflecting both the history of Kendall Square and its future of innovation. A mixed-use building, Site 3 incorporates the existing structure at 238 Main Street (known as the Kendall Building) with a 12-story addition providing new commercial laboratory and office spaces. At the main entrance, a front-to-back five-story atrium brings natural light inside the structure and connects the lower masses of the existing building and the new addition. The building’s ground floor offers retail opportunities on Main Street, Hayward Street, Wadsworth Street, and along its southern side, expanding on existing retail activity in this area. The design, which allows for maximum visual transparency between the sidewalk and retail spaces, optimizes pedestrian flow in and out of the building.