This picture is of a traditional Navajo dwelling. What is it called?

A hooghan (hogan) is the primary, traditional dwelling of the Navajo people. Hooghans can be round, cone-shaped, or multi-sided; with or without internal posts; timber or stone walls and packed with earth in varying amounts. The door faces east to welcome the rising sun for good wealth and fortune.

Today, while some older hooghans are still used as dwellings and others are maintained for ceremonial purposes, new hogans are rarely intended as family dwellings.

Traditional structured hogans are also considered pioneers of energy efficient homes. Using packed mud against the entire wood structure, the home was kept cool in summer by natural air ventilation and water sprinkled on the dirt ground inside. During the winter, the fireplace kept the inside warm for a long period of time and well into the night. This concept is called thermal mass.