Thrill seekers edge walk on Toronto's CN building. Extreme action for extreme attraction lovers. It's one of the world's tallest buildings and stands 116 storeys high above ground. Visitors walk in groups of six attached to an overhead safety rail via a trolley and harness system. There are trained edge walk guides for support who help people push their limits and encourage them to lean back over Toronto to absorb the stunning views of Lake Ontario beneath them. Crazy and breathtaking.