One of the highlights of my trip to Sudbury, ON, was the visit to the Inco Superstack. The tour guide from the City of Sudbury informed us that although the Superstack has been decommissioned, there are no plans yet to demolish the Superstack.
Since there is already an elevator and steel ladder inside the stack between the inner concrete shell and the steel liner, an addition of a secure observation platform at the top would turn this industrial symbol into an iconic tourist attraction.