Ghaghara

The Ghangara is the longest river in Nepal. In Sanskrit, the name means "marbles of the water". Other names of the river are Ghāghrā, and "Gogra. It has a length of" , or including source rivers. Of this length, are in Nepal, where it is called Karnali. It is the biggest tributary to the Ganges by volume, and the second-longest, after Yamuna. 
The lower part of the river, in India, is also known as Sarayu.