The Nile flows northwards. The Egyptians and the Greeks noted this with curiousity. Eratosthenes made use of that fact to measure the circumference of the Earth more than 2000 years ago. We can still learn something from this mighty river. It is originated at equator and flows directly northwards (as accurately as possible for a river) towards the Mediterranean at 30°N. Let us have a look at Google map:
Why on Earth did Nile choose this path? Actually, it can be explained. Rotation of the Earth actually directs it directly northwards, but the mechanism involved can only be understood in context with the convection rolls of the mantle. The symmetry of polygons creates a tectonic path aligned NS. The special condition along equator of weather and tectonics combined create the origins. The estuary is also at a special point, but that has to be explained separately with a map:
The two layers of convection rolls between 120-410 km depth form a holistic circular path (mathematically according to horizontal cylindrical projection). The path shown also represents the division line of the large cells of lower mantle. The backflow (strongest mantle backflow line) is found to pass the estuary of the Nile.
This can be compared with the estuary of Amazon river, found exactly at the division point of large cells along equator.