Sandelie Mud Run
You might think a golf course is an odd choice for a 5k/10k run, but if you like trail runs, this is a great early year event for you. It's called a mud run because chances are you'll get a little muddy running through the Sandelie Golf Course near West Linn, OR. From the organizer: "All race day conditions are provided by Mother Nature. Extra mud will not be added. If it has been raining a lot, expect to get a little muddy."
There is a 250 participant limit to this event so sign up early to ensure your spot. And check your local weather reports.