Template:Main Page/Historic byways/May

• May 1, 2006 – The 10-mile (16 km) portion of NY 17 from I-81 in Binghamton east to NY 79 in Windsor is designated as part of I-86 following the elimination of at-grade intersections and the reconstruction of exit ramps along the stretch
• May 3, 2006 – A new span of the Thomas A. Edison Bridge carries traffic of the Garden State Parkway over the Raritan River, as the old stretch is closed to be rebuilt
• May 9, 1980 – The southbound span of the Sunshine Skyway Bridge carrying Interstate 275 across the Tampa Bay in Florida partially collapses after being struck by a ship, killing 35 people.

• May 12, 1971 – A gap in New York's stretch of Interstate 84 from NY 311 to NY 22 is bridged
• May 14, 1969 – The final section of Interstate 5 in Washington, between Everett and Marysville, is completed and opened to traffic.
• May 15, 1969 – I-690 is extended from the Onondaga Interchange to Midler Avenue
• May 16, 1957 – The Walt Whitman Bridge is opened between New Jersey and Pennsylvania, later to carry I-76
• May 17, 1949 – The William A. Stickel Memorial Bridge opens over the Passaic River from Newark, New Jersey, the first section of NJ 58 to open

• May 20, 2009 – All spans of the Thomas A. Edison Bridge are opened, allowing 15 lanes of Garden State Parkway traffic to cross the Raritan River in New Jersey
• May 21, 2003 – The final section of Delaware Route 1 between Smyrna and Odessa opens to traffic
• May 23, 1956 – The Delaware River Turnpike Toll Bridge is opened, carrying the Pennsylvania Turnpike over the Delaware River
• May 24, 1962 – A section of New York's Quickway is extended from Dunbar Road in West Windsor east to Damascus
• May 24, 1973 – The U.S. Route 222 bypass of Kutztown, Pennsylvania opens to traffic
• May 25, 1973 – Interstate 481 is extended north from NY 5 to the New York State Thruway
• May 26, 1955 – A new bridge across New Jersey's Passaic River extends the Garden State Parkway from US 46 in Clifton to the same in Elmwood Park
• May 26, 1959 – New York's Berkshire Connector is extended from US 9 to the New York State Thruway, completing the spur
• May 26, 1961 – Two bypasses of Glens Falls, New York are opened: a new arterial around the northern and eastern extents of the village, called Quaker Road, and a western bypass from US 9 north to Gurney Lane near NY 149, part of the Adirondack Northway
• May 26, 2002 – Freight barges strike the bridge carrying Interstate 40 over the Arkansas River near Webbers Falls, Oklahoma, causing it to collapse
• May 27, 1955 – The New York State Thruway is extended from Harriman to Hillburn
• May 27, 1977 – Two sections of Interstate 78 in New Jersey are linked with the opening of a section from the Garden State Parkway to the New Jersey Turnpike
• May 28, 1965 – A bypass of Lake George, New York is completed when the northbound lanes of the southern section of the Adirondack Northway are extended to NY 9N, part of which was later downgraded to a reference route when the freeway was redirected to a more northeasterly alignment upon its extension
• May 28, 1982 – New York's Interstate 88 is extended to its eastern terminus at the New York State Thruway
• May 29, 1964 – A section of New York's Quickway is extended from McClure to Hale's Eddy