The fastest land snake in the world is the much feared black mamba (Dendroaspis
polyepis) of the eastern part of tropical Africa. There are many stories
of this species overtaking people on galloping horses but, although moving
snakes do give an illusion of speed, such stories are greatly exaggerated.
However, top speeds of 16 - 19Kmh (10 - 12 mph) have been recorded for black mambas in short bursts over level ground - certainly fast enough to catch up with a person on foot - and speeds of 10 - 11Kmh (6 - 7mph) are probably not unusual.