Ontario provincial highway 11 is one of the longest of Ontario's King's Highways, with a current length (as of 2004) of 1636 km. Highway 11 begins at Highway 400 in Barrie, and stretches across northern Ontario, around Lake Superior, to the Ontario/Minnesota border at Rainy River. At that point it connects to Minnesota State Highway 72 . West of North Bay, Highway 11 is part of the Trans-Canada Highway.

Highway 11 was originally constructed as a trunk road to connect the communities of northern Ontario, and was initially planned to run from North Bay to Cochrane. Construction began in 1925, and it was officially opened on July 2, 1927. When it was opened, it was named the Ferguson Highway, in honour of Premier George Howard Ferguson.

Over the years, Highway 11 grew to stretch from downtown Toronto all the way to the Minnesota border. Highway 11 became synonymous with Yonge Street, the name of the street in Toronto which formed its southernmost segment. It is from this that Yonge Street gained notoriety as the "longest street in the world". In 1997, the portion of the highway south of Barrie, including Yonge Street, was downloaded by the provincial government to various regional governments as part of a mass downloading by the Ministry of Transportation of Ontario. Along with the name Yonge Street, the section in York Region is now York Regional Road 1, the section in Simcoe County is now mostly Simcoe County 4. Toronto does not have a regional road system; it is now only known as Yonge Street there.

Major reconstruction of Highway 11 has taken place in recent years, which has slowly been in the process of upgrading from a two-lane rural highway, to a four-lane mixed expressway, to a 400-Series standard freeway (which has been completed in several sections). By the mid-2010s, it is expected that most, if not all, of the highway between Barrie and North Bay, will be a full freeway.

Highway 11 between Barrie and Gravenhurst is currently a rather unusual right-in, right-out (RIRO) expressway (local access permitted, turnarounds via special interchanges), except for a section around Orillia which is a full freeway. It is expected that the RIRO configuration will be eliminated within 5-10 years as the highway reaches capacity and requires widening to six lanes, which will be a full freeway on or near the current alignment.

North of Gravenhurst to North Bay, freeway sections exist from south of Bethune Drive (Exit 175) to Muskoka Road 117 (Exit 193), from Muskoka Road 3/Aspdin Road (Exit 219) to Novar Road (Exit 235), from Lindsay's Hill Road to south of Proudfoot Road and from Highway 654 (Exit 329) to Highway 17 (Exit 344). Most other sections are of expressway grade with proposals to be upgraded to freeways, although some 2-lane highway still exists between South River and Emsdale ; that section is expected to be widened by 2010.

(Note the exit numbers start around 104 - currently the first posted exit number is 129 in Orillia - presumably for continuation from Highway 400)

Interchanges from South to North

• *Exit number not signed, based on kilometre post
• **Current RIRO expressway section, possible interchange on new freeway

See also

• List of Ontario provincial highways
• Trans-Canada Highway
• Yonge Street