I ran exactly at the noon today, which was not very wise since the sun was striking my head like a hammer. But I managed to run 10 laps for 13:45. I was told that the inner circle of the lap is 230 m and outer is 280 m, so I guess I run 250 m per lap, which makes 10 laps = 2.5 km.
Yesterday early in the morning an asteroid 2004 XP14 flew close (433000 km) to planet Earth. I am grateful it did not hit my running path - it is so difficult to find one where you know exactly how many meters is one lap :)