After crossing the canal via the Sagamore Bridge, US 6 becomes a freeway, known as the Mid-Cape Highway. From the Sagamore Bridge to exits 78A and 78B, the freeway comprises four lanes. The bridges from the Cape Cod Canal to Oak Street in Barnstable (a half-mile [] west of exit 68), are unusual in their construction since they are made out of concrete and granite. The road then reduces to a two-lane freeway with plastic stanchions posted on a small asphalt median. The two-lane freeway section has a secondary, less-formal name of "Suicide Alley", due to the high number of fatalities from head-on collisions before the median improvements were constructed from 1989–1992. The Mid-Cape Highway carries a speed limit of on the four-lane section and on the two-lane section. It remains like this until Orleans, where the freeway ends at a large rotary. Through Eastham and North Truro, US 6 is a four-lane surface street once again. Through Wellfleet and southern Truro, US 6 is a former three-lane road converted to two lanes with broad shoulders. In Provincetown, the road is locally maintained, and ends as a surface expressway before meeting Route 6A at the Cape Cod National Seashore. For the last several miles in Provincetown, eastbound US 6 is actually heading west-southwest. History New England Route 3 Before the U.S. Numbered Highway System, the route from Rhode Island to Bourne, and from Orleans to Provincetown, was part of New England Route 3 (Route 3). Within the Upper Cape, however, Route 3 went along what is now Route 28 between Bourne and Orleans. The US 6 designation was instead applied to the route on the north shore of Cape Cod, which was known as Route 6 before 1926 (now Route 6A). Prior to the building of I-195, the Fall River portion of US 6 followed a different alignment. After entering the city via the Brightman Street Bridge, the route followed Davol Street to Turner Street, where it split to Durfee Street, a short portion of South Main Street and Pleasant Street (eastbound) and North Main Street to Bedford Street to Eastern Avenue (westbound, in reverse order). Both routes then took Pleasant Street east of Eastern Avenue to McGowan Street, which crossed into Westport and joined the current alignment of US 6. The current alignment of these streets would be impossible now, as Turner Street's connection to Durfee Street is blocked,