Oh dear...
For St. John's, you have to be right downtown to see it. The entrance to the harbour, the Narrows, is, as the name implies, too narrow to see much of the city from outside the harbour. And the hill that downtown is built up against is taller than our tallest buildings so you can't see them as soon as you're over the top of it, which is just a couple of blocks away.
The Confederation Building is visible from farther away, as far away as Red Cliff (which is about 10 km), but that's not part of our downtown skyline.