Yo

Yo stands beside the Komadugu Yobe, the river that flows east toward Lake Chad. In descriptions of Bornu, the river formed part of the boundary of the kingdom's heartland and was sometimes named after the town. Farther upstream its waters gather from rivers that descend through the Hausa country, before crossing the dry plains toward the lake. Along this course, Bornu's settlements faced the neighbouring lands to the north and west.

The later city of Diffa lies here.