Toronto’s commercial business district (CBD) has been a few centuries in the making, at one point, it contained the tallest building in the British Dominion. Fast-forward many decades and it became a canvas where Ludwig Mies van der Rohe and then I.M. Pei tested ideals of the future city. Today, it is one of the top 10 financial centers in the world, second in North America, and the fastest-growing tech economy on the continent. It features a vast underground pedestrian concourse and an interconnected deep-water heating and cooling system. And it continues to grow and evolve. A second CBD, the South Core, has sprung up south of the rail tracks. It features a noticeably different approach to workspace and commerce. The tour will visit many iconic buildings and plazas while trying to dissect their contribution to city building and to Toronto’s economy.