The Nyakagezi rises in the south of the Sankinyinya colline of the Commune of Gahombo, Kayanza Province, and flows east.

To the north of the Nyamugari Colline of the Commune of Ruhororo the Nyakagezi turns northeast.

[4] The surroundings of Nyakagezi are a mosaic of agricultural land and natural vegetation.

[5] The area is densely populated, with 442 inhabitants per square kilometer as of 2016.

The warmest month is September, when the average temperature is 21 °C (70 °F), and the coldest is April, with 17 °C (63 °F).