Though it's been around for more than 30 years, the funky CN Tower still warrants 'icon' status. Its primary function is as a radio and TV communications tower, but relieving tourists of as much cash as possible seems to be the second order of business. It's expensive, but riding the great glass elevators up the highest freestanding structure in the world (553m) is one of those things in life you just have to do. On a clear day, the views from the Observation Deck are astounding; if it's hazy, you won't be able to see a thing. Beware: two million visitors every year means summer queues for the elevator can be up to two hours long – going up and coming back down. For those with reservations and sacks full of cash, the award-winning revolving restaurant 360° awaits (with 'the world's highest wine cellar'). Elevator price is waived for diners.