[3][6][7][8] Having been called the "cradle of the French Canadian nation," the heritage site includes approximately 350 buildings along 3.5 kilometres (2.175 miles) of the Saint Lawrence River shoreline.

[5][9][10] The Sillery Heritage Site includes buildings constructed during every major period of Quebec's history, dating back to the time of New France.

Heritage designation began as early as 1929, when the Jesuit House was assigned protective status.

[4] While recognizing the visionary action taken by Quebec's Ministry of Culture (French: ministère de la Culture), in the 1960s, by conferring historic status upon the district to protect it from suburban developers, the National Trust for Canada (French: Fiducie nationale du Canada), a national registered charity in Canada, placed the Sillery Historic District on its Top 10 Endangered Places list (French: Palmarès des 10 sites les plus menacés), in the early 2010s, due to the approval of condominium developments which encroached upon historic religious properties in the district.

The city argued that some development was necessary to provide tax revenue in order to sustain the preservation of the historic district.