Waterloo Regional Road 4

Waterloo Regional Road 4 is an arterial road located in the Region of Waterloo, Ontario, Canada. It is a major east-west thoroughfare through the city of Kitchener, where it is known as Ottawa Street. Despite running east-west, Ottawa Street is labeled north-south, with King Street being the dividing line. Upon passing Trussler Road westward out of Kitchener and entering Wilmot Township, Waterloo Regional Road 4 is renamed Bleams Road.

In Kitchener, Ottawa Street intersects the Conestoga Parkway at two points. However, only the first intersection on Ottawa Street North (between the Freeport Diversion and Highway 7) is served by a full signed interchange. The second intersection, on Ottawa Street South west of the Freeport Diversion, must be accessed via the Homer Watson Boulevard interchange.

Three major shopping centres are located along its route. Stanley Park Mall is situated on Ottawa Street North at the intersection with River Road. Ottawa Street South is the home of two power centres: the Sunrise Shopping Centre is located at the intersection with Fischer-Hallman Road, while the Laurentian Power Centre is at the intersection with Homer Watson Boulevard. Ottawa Street South is also the site of the Concordia Club, a major "festhalle" which hosts up to 4,000 revelers during Oktoberfest each year.