Work is underway on a new public art installation in downtown Calgary by world-famous artist Jaume Plensa.

Barcelona-based designer Plensa has been hired by the city of Calgary to create two sculptures in front of The Bow building.

One piece will be a bronze cast of the artist embracing a real, live tree. The other sculpture will be a 12-metre tall steel mesh head of a girl called Wonderland.

"The piece is a head of the young girl with the possibility of people to walk inside," Plensa said. "It has two entrances, one on each side of the head and people are allowed to walk inside the head and to try dream about how the head is from the inside."

Plensa's public art sculptures can be found around the world. One of his most famous works is the Crown Fountain in Millennium Park in Chicago.

It will take two months to install the artwork.