As you approach the city, whether by plane, train, or automobile, the first thing you notice is this slender structure. Glass-walled elevators glide up the 553m (1,815-ft.) tower, the tallest freestanding structure in the world. The elevators stop first at the 346m-high (1,136-ft.) Look Out level. (It takes just 58 seconds, so prepare for popping ears.) You can walk down one level to experience the Glass Floor, my favorite spot at the tower: Through it you can see all the way down to street level (even as your heart drops into your shoes). As a bonus, if you wait long enough, you'll undoubtedly see some alpha males daring each other to jump on the glass. (They do, and no, it doesn't break -- the glass can withstand the weight of 14 adult hippos. Now that's a sight I'd like to see . . .)

The tower attractions are often revamped. Some perennial draws are the IMAX theater and two airplane simulators (one gentle and calm, the other a rugged ride through caves and over mountains). A series of interactive displays showcases the CN Tower along with such forerunners as the Eiffel Tower and the Empire State Building. The Look Out also contains broadcasting facilities, a nightclub, and the underwhelming 360 Revolving Restaurant.

Above the Look Out is the world's highest public observation gallery, the Skypod, 447m (1,465 ft.) above the ground (C$7/US$4.90 additional charge). From here, on a clear day you can't quite see forever, but the sweeping vista stretches to Niagara Falls, 161km (100 miles) south, and to Lake Simcoe, 193km (120 miles) north. Unless you're really taken with the tower, I wouldn't recommend it -- the view from the Glass Floor is majestic enough for me. Atop the tower sits a 102m (335-ft.) antenna mast erected over 31 weeks with the aid of a giant Sikorsky helicopter. It took 55 lifts (and no hippos) to complete the operation.