As with ME 11, ME 9 was once a small NEI expanded out to a major cross-state
arterial. As NEI 9, the highway only reached Wells and as such barely entered
Maine's south with an in-state length of just 18 miles. Today, however,
ME 9 is a significant alternate to US 1 and a major route in its own right,
extending all the way to Calais and the Canadian border.
ME 9 did not achieve its current length until the Maine Great Renumbering,
when it was extended from Wells along old ME 218 to Kennebunkport,
new routing to near Biddeford Pool and most of ME 208 to Biddeford,
then up to Saco and out to the coast and back to Scarborough along that
portion of old
ME 205, through Portland
(briefly with ME 22, then new routing along Stevens Ave, Walton St and Ocean
Ave), then new routing through North Yarmouth and Pownal to Sabattus, cosigned
with ME 126 from there to Gardiner, using new routing on the east shore of
the Androscoggin up to Augusta, joining ME 3 there up to South China where
it continued along old ME 138 to Hampden via Unity and Dixmont, and then
US 1 (now US 1A) into Bangor.
From Bangor, it exited via ME 178 and took over ME 179
to Aurora, the Air Line Road between
Aurora and Wesley, and finally the northern portion of ME 192
to Baring Plt where it ended at US 1. This terminus persisted
until the mid-1990s
when it was finally co-routed over US 1 into Calais and capped at
the international line.
There have been multiple minor realignments of ME 9, most recently 2007's
slight re-route within Portland (shifting it to Woodford St and Forest Ave
instead of Walton St), partially triplexing it with US 302 and ME 100.
Although this routes the highway into the very
busy Woodfords Corner, it avoids the residential neighbourhoods along
Walton St and shortens the route by around 0.4 mile (Eric Bryant). The
route log mileage above does not reflect this change.
Much of ME 9 between Augusta and Hampden was cosigned with US 202 after
its birth in the state; see US 202 for realignments pertaining to that
ME 9 is a multi-state route with New Hampshire; see also ME 4,
ME 11, ME 16, ME 25, ME 26, ME 109 and ME 110.
See also ME 9B, ME 9A and ME 9W.