The Major-General George R. Pearkes Building (often abbreviated as just Pearkes and referred to as '101 Col By') is the principal location of Canada's National Defence Headquarters (NDHQ) and is located in downtown Ottawa, Ontario. NDHQ comprises a collection of offices spread across the National Capital Region, however it is primarily based at Major-General George R. Pearkes Building at 101 Colonel By Drive in Ottawa.
The building is currently occupied (as of 2022) by senior defence and military staff, procurement and policy officials, intelligence specialists, legal affairs and staff involved in infrastructure.
The building, named after Major-General G.R. Pearkes, was constructed between 1969 and 1974, and was originally intended for use by the Department of Transport. When a planned National Defence Headquarters complex on the LeBreton Flats was not built, however, DND acquired the Colonel By Drive structure. In 1972, the Department of Transportation moved into Place de Ville's newly completed Tower C.
The concept for the group of buildings was developed by French town planner Jacques Gréber immediately after World War II at the invitation of Prime Minister William Lyon Mackenzie King. Gréber, a proponent of boulevards and highways as opposed to rail corridors, advised that the city redevelop the east bank of the Rideau Canal which was, at that time, covered with railway tracks leading to Ottawa Union Station.
This design was accomplished with the removal of the station tracks and relocation of passenger rail service to a new suburban station; the Ottawa Union Station building has since become the Government Conference Centre. The remaining land that contained the coach yard for Ottawa Union Station was vacant and ready for developments that would contain the Pearkes Building and the Rideau Centre.
Architects John C. Parkin, Searle, Wilby, and Rowland designed the buildings in the then-popular Brutalist style. They were conceived as the first phase of the planned redevelopment, the Rideau Centre, which opened in 1983, being the second phase.
