Experience Northfield. Northfield is a vibrant Minnesota city situated in the Cannon River Valley just south of the Twin Cities metropolitan area - an ideal location that combines small town living with a convenient 30-minute drive to big-city amenities. Northfield is a growing community of 17,500 with a lively historic downtown, two prominent colleges, a strong public school system and a diversified economy. The city boasts over 35 parks, many civic organizations and clubs, numerous opportunities for involvement in the arts and athletics, as well as annual community-wide programs and celebrations. Our Office Is Located Off-Site, Please Call For Directions. Northfield is located 7 miles east of Interstate 35 and 20 miles west of U.S. Highway 52 on State Highway 19. State Highway 3 runs north and south through Northfield and intersects with State Highway 19. Major employers include St. Olaf and Carleton Colleges, Malt-O-Meal.