Google Map PLugin or site slow to load

My site is extremely slow to load. On the following link the google map will take up to 2 minutes to load.

http://peakorthotics.com/affiliated-clinics-in-ab/ (click on Calgary and wait for map)

I have ran Hummingbird cache and GZip but it makes no difference. Have not run Minification as don't want to bring down the site.

When I load any page it will show quickly but the spinning loading sign on the browser continues to spin for a long time.

Anyone please help?