Thousand Islands Parkway

Thousand Islands Parkway
St. Lawrence River Road
Thousand Islands Parkway highlighted in red
Route information
Maintained by the St. Lawrence Parks Commission
Length	39.1 km[1] (24.3 mi)
History	Opened in 1938 Numbered Highway 2S in 1948 Renumbered Highway 401 in 1952 Renumbered Highway 2S in 1967 Decommissioned September 8, 1970[2]
Major junctions
From	Highway 401 west in Gananoque
Major intersections	Highway 137 to Thousand Islands Bridge to the United States
To	Highway 401 east near Butternut Bay
Location
Country	Canada
Province	Ontario
Highway system
Parkways of the Great Lakes Long Sault Niagara St. Clair 1000 Islands Roads in Ontario
← Highway 2 → Highway 3
Former provincial highways ←  Highway 2A

The Thousand Islands Parkway (often written as 1000 Islands Parkway) is a scenic parkway in the Canadian province of Ontario. It extends easterly from an interchange with Highway 401 in Gananoque for approximately 40 kilometres (25 mi) to rejoin Highway 401 near the community of Butternut Bay, west of Brockville. The parkway follows the north shore of the St. Lawrence River, and was formerly designated Highway 2S (S for Scenic) until 1970. It passes through the communities of Gray's Beach, Halsteads Bay, Ivy Lea, Darlingside, Rockport, Narrows, La Rue Mills and Mallorytown Landing, as well as providing access to the three inland properties of the Thousand Islands National Park. Highway 137, which meets the parkway near its midpoint, provides access to the Interstate 81 in New York via the Thousand Islands Bridge.

The Thousand Islands Parkway was constructed as a divided highway during the late 1930s, alongside the Thousand Islands Bridge, which opened in 1938. Originally known as the St. Lawrence River Road, the parkway became part of Highway 401 when the 400-series highway system was established in 1952. However by that time numerous properties and tourism had been established which made the parkway difficult to upgrade to a full freeway, so in 1968 Highway 401 was rerouted along a new alignment (the Thousand Islands Bypass) north of the existing parkway. The Highway 2S designation returned between 1967 and 1970, after which jurisdiction over the parkway was transferred to the St. Lawrence Parks Commission. The northern carriageway of the parkway was never paved, and was only in use by vehicles between 1938 and 1951. Evidence of its former use can be seen today in the wide right-of-way; the unused westbound lanes now serve as a recreational trail and twin bridges span two locations along the parkway.