Achernar ("the end of the river") is a bright bluish star which in fact does represent the end of the great celestial river Eridanus, which - if you live in the Northern Hemisphere - is seen to begin to flow at the foot of Orion.

While the star is invisible for most of the Northern Hemisphere, it is a fine Spring and Summer star for the Southern Hemisphere, to the west of the brightest star in the Southern Hemisphere, Canopus.

If in fact you live in the Southern Hemisphere, you can interpret the constellation differently: Achernar being the beginning of the great river, as it flows north to finally end at the foot of Orion.

The constellation is roughly north-south at midnight in the last week of November.