There is a lot of information out there about this annual event, and most of it is related to the river Mara crossing into Kenya. Please find more information about this amazing migration here on the official Tanzania site.
As an European who never witnessed this before, it was astonishing to just drive around the northern Serengeti this time of year. There is no escaping Wildebeest, they are everywhere, normally in loose herds, spread out. But then the pressure builds up and they need to “go on” towards their next destination and this means crossing a river.
We spend 4-5 hours early in the morning observing a crossing of a herd around 100.000 strong. This was no longer a spread out herd, but a dense, high pressure event, where they were probing different ways to cross the river, some going in at one place, others at another to find a safe passage. The more a group was successful, the more pressure build up.
