Construction workers have started building a new multi-use development on the site of the old Boston Garden.
A groundbreaking was held Wednesday for the 1.5-million-square-foot development called The Hub on Causeway, next to the TD Garden and North Station.
Delaware North and Boston Properties plan retail, office and residential space on the 2.5 acres site, as well as a 260-room hotel.
The development will include a supermarket for the underserved neighborhood, a 15-screen movie theater and a 540-space underground parking garage.
Mayor Marty Walsh says the development will have a "transformative effect" on the area.
As part of the $950 million project, the TD Garden sports arena will also undergo some changes, including a 64,000-square foot expansion of the third through ninth floors.