If you've been to the airport lately, you can't miss all the construction underway. It's the largest expansion ever at Calgary's airport.

415 workers are on-site, around the clock.

Five construction cranes fly material across the site.

On the north side of the existing terminal, construction is underway on the new YYC international facility, which will eventually hande all of the airport's out-of-country traffic.

"It's approximately two million square feet. The existing terminal building is a little bit more than 1.5 million square feet, so it will more than double the terminal space at the airport," says the Calgary Airport Authority's Bob Schmitt.

When it's done, it might seem more like a mall than an airport.

Plans call for a glass roof over polished granite flooring with high-end merchants flogging their wares to international travelers.

Underfloor heating will be delivered by over 600 geothermal wells drilled on the site.

Right now, Calgary's airport averages almost 35,000 travelers a day.

"All the facilities are at capacity so we have a number of challenges meeting the demand that we currently have. So the new terminal will accommodate all that future demand as well as the current demand that we have," says the authority's Jody Moseley.

The new air traffic control tower will open this fall, a new runway in spring 2014 and the 22 gate international facility will open in the fall of 2015.

The new runway will be the longest commercial runway in Canada, at over 4.2 kilometres in length.