Discussion: Carburn Park course length

The course includes the distance around the lakes (800m extra), but not extra distance in the residential area. I used 1:7500 as the scale, however, I think it's wrong. I double checked the length and there is NO way that it is 8.3 Km. Does anyone have a solution?

There. I checked with the city map and the scale is 1:5562. The course is now only 5.9 Km