It's generally fun to observe. When I've seen ISS, it has been around sunset. It is a readily discernible point of light, in my memory brighter than Venus and certainly brighter than any star, that moves from horizon to horizon in only about 4 minutes ("faster than a speeding plane"), even less time considering trees, buildings, and hills.<p>Because of the speed, it is helpful to know what place on the horizon the overpass will start at, in addition to the precise time.