To find the circumference of a circle, you can use the formula:
\[ C = \pi \times d \]
where \(C\) is the circumference and \(d\) is the diameter of the circle.
Given that the diameter \(d\) is 8 kilometers and using \(\pi \approx 3.14\), we can calculate the circumference as follows:
\[ C = 3.14 \times 8 \]
Calculating this gives:
\[ C = 25.12 \]
Therefore, the circumference of the circle is approximately 25.12 kilometers.