 Springfield's most popular tourist attraction, the riverfront Basketball Hall of Fame, is separated from Metro Center by a stone wall, buttressing an elevated portion of the six-lane Interstate 91, and greatly discouraging travel between the two areas.Academic suggestions that involve the demolition of the current highway and moving it to a less obtrusive site in the city have been proposed, including the demolition of the highway and following the original path suggested, Riverdale Road, and, least obtrusive but still requiring a great deal of work, a plan to construct numerous walkways beneath the elevated highway to better integrate the neighborhoods with the waterfront despite the highway's presence.All interchanges in Massachusetts were to be renumbered to milepost-based numbers under a project scheduled to start in 2016.