COP, Calgary, AB
There's a weekly race series running Thursday nights at COP eastlands:
Cost: $15 online, or $20 on-site
Race start time is 7pm, registration opens at 5:45. Pretty casual event, no racing license required. Just show up and pedal your guts out :) There's also a trail running race if that's your thing.
A few of us went last week and had a good time. There were free Honey Stinger snacks, free beer, and a few draw prizes after the racing.