<p style="text-align:justify">Lake Hantsongoma, a small permanent crater lake, is located at 950 m above sea level at the northern foot of Karthala, between the mountains of Bahani in the Itsandra region and Irohé in the Wachili region.</p>
<p style="text-align:justify">This is the northeastern slope of the Karthala forest. The lake is located at an altitude of 1,060 m, and in 2002 had a perimeter of 800 m and a maximum depth of 2 m. In 2010, the perimeter was 285 m with a depth of 1 m. It is located between the humid forest to the west, and the dry forest to the east. It is the only freshwater lake on the island of Ngazidja.</p>