This week, the Sears Tower in Chicago opened up a set of glass boxes that jut out from the side of the building. Visitors stepping out onto the glass floor of the boxes will find themselves standing 1,300ft. (396 meters) over the city streets. It’s definitely not for the faint of heart or for folks afraid of heights, but for everyone else it’s a great way to get a thrilling and unique view of the city. However, it’s not the only place where people can “walk on air” to get a great view of a place.

Grand Canyon Skywalk– In 2007, the Hualapai tribe opened a glass walkway that juts out over the Grand Canyon in Arizona. Visitors seemly step off an edge of a cliff and find themselves standing 4,000 ft. (1,219 meters) above the Colorado river. Most glass floors are located on towers, so this skywalk is unique in its canyon location. It’s also the highest skywalk in the world.

One of the Tokyo lookdown windows. Photo by Torsodog.

One of the Tokyo lookdown windows. Photo by Torsodog.

CN Tower– This tower in Toronto, Canada has the world’s highest glass elevator at 346 meters (1,135 ft.) tall. It also has the highest glass floor located in a tower.

Calgary Tower– Further west in Canada is the Calgary Tower. It has a glass floor that’s 36 ft. long and 4 ft. wide and is located 525 ft. (160 meters) in the air.

Shanghai World Financial Center– This skyscraper has the highest observation deck in the world. It also has a  glass skywalk on the 100th floor.

Tokyo Tower– The tower has two sections of floor that are made up of glass to create “lookdown windows” so visitors can see the base of the tower.

Eureka Tower– Located in Melbourne, Australia, the tower has a feature called “The Edge”. It’s a large glass box that moves out 3 meters (10 ft.) from the side of the building. The one downside of this attraction is that cameras are not permitted on the ride.

Several other towers also have glass observation decks including the curvy Spinnaker Tower in Porthmouth, England; Blackpool Tower in Lancashire, England; and the Sky Tower in Auckland, New Zealand.

Flickr also has a nice set of photos of glass floors from around the world at the “On the Glass Floor” photoset.