The Seneca One Tower would be barely visible from the top of the CN Tower, though the CN Tower is more visible from the top of the Seneca One Tower.I believe you can pick up Niagara Falls on a clear day too.
I believe I remember seeing somewhere that Buffalos tallest building should theoretically be*just* visible on the horizon as well from high up, but it’s so far away you need a really clear day to see it. You need curvature of the earth calculations to figure that one out though.
GIFed. Had to drop a few frames that weren't aligned to my liking so it takes a bit of a dramatic jump in the last few frames:
For those of you are familiar with Johnny Strides work. This guy rides and walks all over Toronto's streets, parks and everything in between. He's created a video walking around Bremner Boulevard, Harbour St. etc. Video taping One Yonge project and the LBCO area etc. The video is called downtown Toronto south core walk November 17 2020 on the Johnny Strides blog. If someone can display it here on Urbantoronto.ca One Yonge. It would be nice to see for those who don't know how upload it thanks!