The standard loop is 10km.

Place of confusion: The course is well marked and easy to follow, but every year we have a couple of people make the same error, only one mile into the course - MAKE SURE YOU CROSS THE 7IL DRIVEWAY AT THE UNMANNED WATER STATION. This section is two-way traffic of inbound/outbound runners. You must go all the way out to Hot Tamales before coming back to the start/finish. 

135M/26.2M/13.1M: Have an additional add-on at the start of the loop, look for signs for your event, follow pre-race instructions.