The foot of Morningside is located at Guildwood Parkway on the shores of Lake Ontario, and traces the original Scarborough TownshipLot 10 line north-east toward the commercial centre of the West Hill neighbourhood at Kingston Road. West Hill takes its name from its position above the broad valley of Highland Creek. The valley is the site of Morningside Park, one of Toronto's largest. Within the valley at the intersection of Ellesmere Road is the Morningside Campus of Centennial College and the Scarborough campus of the University of Toronto in which Morningside Avenue forms the western boundary of. Beyond the valley, which was the former northern terminus, the present route was named "Littles Road" after an early family in the area. Between Sheppard and Finch Avenues, Morningside serves as the eastern boundary of the Malvern neighbourhood. The route veers to the north-west north of Sheppard Avenue, skirting the ravine of Morningside Creek and Rouge Park. Communities lining the northern reaches of the street, and those nearby across the city boundary in Markham, are constrained by the topographic and legislative boundaries of Rouge Park. A northern extension to Morningside Avenue was proposed, traversing the Brookside and Morningside Heights neighbourhoods to connect with the exurban community of Box Grove. These plans have since been canceled due to concerns that the extension would necessitate construction in a sensitive section of Rouge Park. The low, narrow, one-lane railroad underpass at Finch Avenue, dating back to when it was a rural road, was replaced in 2009, allowing 4 lanes of traffic to pass below uninterrupted. McNicoll Avenue was later extended east terminating at a newly built extension of Morningside Avenue, while Oasis Blvd continues east of Morningside Avenue as a residential neighbourhood.
Future
Morningside Avenue is planned to be extended to Steeles Avenue in the future to connect to Donald Cousens Parkway via a widened Steeles Avenue. As of December 2019, the Steeles widening project is expected to start construction in 2022, and although the detailed design of the Morningside extension is expected to be completed in 2020, no schedule has been announced for the extension yet.