East of Brookers Lane, the route geometry of Lake Shore becomes complicated due to the interchange with the parallel Gardiner Expressway; which runs tight up against it to the north near the Humber River crossing: The westbound lanes cross the Gardiner (running along the north side of it) and are intertwined with the ramp from the westbound expressway which meets the street opposite Brookers Lane after crossing back to the south side; although Lake Shore still has an overlapping two-way section east of this point entirely south of the Gardiner.

The splitting of Lake Shore was done at the time of the expressway's construction, as new bridges were built to connect to the terminus of the Queen Elizabeth Way highway.

The highway to the west has become part of the Gardiner, and the Lucky Lion monument which designated its starting point was relocated nearby to the south of the Lake Shore Boulevard, just east of the Humber.

The section east of the Humber was infilled in the 1910-1920s and was part of the Sunnyside Amusement Park development, which the road travelled through.

The Sunnyside/Exhibition section has much open space with some development, including recreation facilities, such as Ontario Place, Sunnyside Bathing Pavilion, Palais Royale and the Boulevard Club.

West of Yonge, Lake Shore is one-way westbound, while eastbound traffic travels along Harbour Street.

In the 1910s, an overpass over the waterfront rail lines was built to connect Queen Street to the Lakeshore Road at Roncesvalles Avenue.

At the same time, Lake Shore Boulevard was extended as a four-lane roadway east to the Exhibition Place area.

In October 1954, the Lake Shore Boulevard bridge over the Humber was destroyed by debris floating downstream in the flooding caused by Hurricane Hazel.

In the 1950s, as part of the Gardiner project, Lake Shore Boulevard east of the Humber was doubled in width by widening into the right of way of Lakeshore Road, replacing it, which resulted in the demolition of the rail overpass leading to the Queen/Roncesvalles intersection by 1960.

Lake Shore Boulevard in the downtown was built to connect Fleet and Harbour Streets and was a service road for the Gardiner.

One of only two regular services, the 80 Queensway bus travels along Lake Shore between Ellis Avenue and Parkside Drive.