The 76.4-kilometre-long (47.5 mi) freeway acts as an important trade corridor from Interstate 81 between New York and Eastern Ontario via Highway 401, as well as the fastest link between Ottawa and Toronto.

The route travels to the east of the community, access to which is provided by an interchange at County Road 21, and crosses a swamp and the South Nation River.

[4] Aside from the first couple of kilometres north of the Rideau River, the majority of the freeway cuts through swaths of farmland which fill the Ottawa Valley.

Approaching urban Ottawa, the route passes alongside a large quarry, then jogs to the west along an S-curve, crossing the Jock River in the process.

[4] After this, an interchange with Fallowfield Road provides access to the suburb of Barrhaven which occupies portions of the land immediately east of the freeway.

[6] The route jogs back to the east along a second S-curve and passes through an aesthetically designed bridge while traveling alongside the Stony Swamp.

It passes beneath Bruin Road and the Ottawa Central Railway while traveling alongside Lynwood Village in Bells Corners.

[4] The Stony Swamp overpass at the southern entrance to Ottawa is a pre-tensioned concrete arch; the design, which allows the structure to cross the entire right of way with a single span, won the 1996 Award of Excellence from the Portland Cement Association.

[11] In the same vicinity, the freeway sinks below ground level in a trench; groundwater-retaining walls were installed to prevent the lowering of the water table in adjacent wetlands, therefore mitigating damage to them.

[12] At the Jock River, southwest of Barrhaven, deposits of sensitive leda clay presented a challenge in designing the crossing for the freeway as well as the Canadian National Railway overpass to the north.

With the intent of reducing the severity of collisions against those cuts, the Ministry of Transportation of Ontario (MTO) tested out numerous alternatives to strike a cost-to-benefit balance.

[16][17] This highway served the low traffic volumes of the day, but as the number of vehicles increased over the first half of the 20th century, issues arose with the numerous private driveways along the route.

[19] The project was completed in 1983,[1] merging into the original route of Highway 16 northeast of the present Prince of Wales Drive overpass.

[22][23] With the completion of Highway 16 New, the MTO needed only to construct interchanges and the southbound lanes in order to create a full freeway corridor.

[5][11] The original plans for Highway 416, conceived during the late 1960s, had it enter Ottawa along the Merivale Corridor to merge with the Queensway approximately five kilometres (3.1 mi) east of the present interchange.

The MTO set out to design a four-lane route to connect the Queensway with Highway 16 New, including a three-level free-flow interchange.

Instead, a hiatus in construction allowed engineers to evaluate inefficiencies in bridge and cross-section designs, as well as sensitive clay soils near Ottawa.

[11] On December 8, 1995, in North Gower, the provincial and federal governments announced a financing deal to ensure Highway 416 South was completed by 2000.

The first was awarded to Tarmac Canada on June 10, 1996, calling for twinning of 7.6 kilometres (4.7 mi) from Century Road south to Roger Stevens Drive.

[5] The section between Roger Stevens Drive and what had now become Leeds and Grenville County Road 43, including a second crossing of the Rideau River, opened to traffic on June 26, 1998.

Premier Mike Harris, Transportation Minister David Turnbull and World War I Veteran James W. Fraser officially opened the highway.

[38] The Ontario government is fighting gridlock in south Ottawa by investing $5 million in a new interchange at Highway 416 and Barnsdale Road.

The interchange will save commuters time in the rapidly growing community of Barrhaven and connect more people to housing and jobs across the region.