Most recent one is called Chinook Arc by Creative Machines in Calgary's Beltline neighbourhood:
http://2.beltline.ca/media/chinook_arc_83942.jpg
https://fbcdn-sphotos-e-a.akamaihd.n...31263051_n.jpg
Wonderland by Jaume Plensa
https://c1.staticflickr.com/9/8228/8...6505d254_z.jpg
A couple temporary ones by Calgary artists Wayne Garrett and Caitlind Brown
Cloud (has been travelling all over the world)
http://www.apowl.co/wp-content/uploa...nd-Brown-1.jpg
And Solar Flare
http://www.calgaryherald.com/cms/binary/9301558.jpg