Ontario Highway 115

King's Highway 115, commonly referred to as Highway 115, is a provincially maintained highway in the Canadian province of Ontario that connects Peterborough with Toronto via Highway 401. The highway begins at a junction with Highway 401 southwest of Newcastle and ends at an at-grade intersection with Highway 7 east of Peterborough.

Highway 115 is part of the Algonquin Trail and is concurrent with Highway 35 from its southern terminus in Clarington to Enterprise Hill, where it veers towards Peterborough and Highway 35 continues north into the Kawarthas. It is also part of the Trans-Canada Highway from the interchange with Highway 7 south of Springville, Ontario to the northern terminus of the highway. Highway 115 is a freeway northeast of Enterprise Hill and a right-in/right-out (RIRO) expressway south of it, featuring short ramps with abrupt right turns to and from the highway. By January 2010, exit numbers were added to the freeway section north of the Highway 35 concurrency.