The Knoll, demolished for the construction of Mull Hall.

The site's initial concessions were granted to Jean Boileau dit Larivière, for lot 161, and François Guimot dit Lalonde, for lot 162.

The Knoll
The land was divided and parcels of lot 160 were acquired, primarily by the Legault family, and redistributed between 1885 and 1891 as a single property – "The Knoll." Thomas Avery Crane, of Crane & Baird Grain Exporters, built an imposing wooden country house by the edge of the lake and began farming north of Lakeshore Road. In 1901 the house and farm were sold to Hugh Andrew Allan, while part of the land was reserved for a tree farm, the Pointe Claire Nursery. Descended from a prominent Montreal family, Allan was instrumental in reorganizing the family business, the Allan Steamship Line Co.

Mull Hall
Charles Wesley MacLean acquired the property in 1911, reassembled the original parcels of land, and set up a model farm. In 1915 MacLean demolished the house and built a new one more suited to his social standing. Through his first marriage to the daughter of Senator Fulford, he became the heir to Fulford Place, the family home of the Fulfords of Brockville. MacLean ordered a larger, but less ornamented, copy of the house from architect Robert Findlay. A Scot, Robert Findlay came to Canada in 1885. From 1890 to 1930 he designed some 30 houses for the Montreal elite along the Golden Mile and in Westmount. Mull Hall was completed in 1916. Its name commemorated the ancestral home of the McLean clan on the Isle of Mull in Scotland.
 
The facade has a symmetrical design modified only by the colonnaded portico at the main entrance. A verandah in the same formal style surrounds the other sides of the building. The house is built of blocks of rusticated limestone purchased from local quarries. The hip roof was originally covered with cedar shingles, now replaced by sheets of ridged copper leaves.

In 1940 the Fathers of Sainte-Croix acquired the property for a noviciate and continued to farm. The sale of the property in the 1950s excluded the four-acres of the estate on which the mansion stands. These were bought by May Beatrice Stewart, who sold them for thesymbolic amount of $1.00 to the city of Pointe-Claire. The mansion was restored in 1962 by architectural firm of Papineau-Gérin-Lajoie-Leblanc. The official opening of Stewart Hall was held on February 16, 1963.