It all depends really on how fast you are going (i.e. what mode of transport)
15km
15km/h
Chickens can travel up to 15km an hour.
15 minutes
About 66 minutes and 40 seconds.
15 kilometers, or 24 miles
750 metres
15km
At 30 mph, it takes 18minutes38.5seconds to cover 15 km.
Just 15km
15km = 9.321mi
About 15km by road.