The Blue Nile Falls are a waterfall on the Blue Nile river in Ethiopia. They are known as Tis Issat in Amharic, when translated, means "smoking water" They are situated on the upper course of the river, about 30 kilometers downstream from the town of Bahir Dar and Lake Tana.
The falls are estimated to be between 37 and 45 meters high, consisting of four streams that originally varied from a trickle in the dry season to over 400 meters wide in the rainy season. Regulation of Lake Tana now reduces the variation somewhat, and since 2003 a hydro-electric station has taken much of the flow out of the falls except during the rainy season. It is considered one of Ethiopia's best known tourist attractions.