First Canadian Centre
First Canadian Centre is an office tower in Calgary, Alberta, Canada. Located at 350 7 Avenue SW in the city's downtown core, it stands at or 41 storeys tall. The skyscraper has a floor area of and was built in the international and late modernist architectural styles. The Bank of Montreal occupies most of the ground floor with a large retail bank branch. History. It was designed by Bregman + Hamann Architects, and was the tallest building in Calgary (surpassing Scotia Centre) when it was completed in 1982. Original plans called for a two tower complex , with this tower being the first of the two tower project. The second tower would have had 64 storeys. A downturn in the local economy at that time forced plans for the second tower to be shelved. However, with the recent boom in Calgary, the vacancy rate in the downtown core has dropped to 0.5 per cent, the lowest in North America. This has created a highly rumoured resurrection of the second tower, as a land use amendment has been submitted to city council for approval. The second tower, at the corner of Seventh Avenue SW and Second Street SW , with a proposed opposite top slope to the first tower, to be 64 stories, was started in 1981, with the pouring of its foundation at street level from both 7th Avenue and 2nd Street. All traffic was stopped by police during the night to allow concrete trucks to reign non-stop along Seventh Avenue. Ten thousand cubic metres of concrete was placed in 26 hours, making it the largest continuous concrete pour in North America at the time. Concrete was supplied from two ready mix plants, approximately eight concrete pump trucks were strategically located along the east and north sides  of the construction site. Twenty 1-metre dia. half pipes placed along Seventh Avenue which were used to place the greatest volume of concrete from street level to the foundation 3 stories below. The large foundation and parking levels still remain covered by a park at street level with the hope for the tower to be constructed in the future. Dome Petroleum was slated to move into the second tower using a large portion of it for its Calgary based operation, nicknaming it "The Dome Tower" prior to its construction. With the National Energy Program slowing Alberta's oil and  gas industry in the early 1980s, Dome's profits were hit hard and caused the company to withdraw from the tower's acquisition, which may have had a large effect for the tower's demise. During the construction of the West Tower, it was rumored that the future East Tower had an "open-ended" design plan that could potentially add extra floors to the top of the tower in order to attain title of the tallest building in Calgary, as the Petro-Canada Tower at Fifth Ave and Centre Street was then under construction and its total height was to  end up being the tallest building in Calgary. The existing East Tower is clad entirely with white-grey marble slabs imported from a quarry in Italy, as was the second tower to be clad identically.