Northeastern University broke ground Friday on its new science and engineering complex, a $225 million project that promises to boost the school’s reputation as a research institution and bridge Boston’s Roxbury and Fenway neighborhoods.

Boston Mayor Marty Walsh was among those who attended the groundbreaking on Columbus Avenue, which will replace a surface parking lot near Melnea Cass Boulevard and the Ruggles MBTA station.

The project on 3.5 acres is scheduled for completion in the fall of 2016. The six-story structure will include laboratories and research space, classrooms, an auditorium and a café.