Haa used to be the gateway to Bhutan in olden days. It is the only district in the country that shares border with both India and China. Also, it is the second least populated dzongkhag in Bhutan after Gasa. The dominant language of the district is Dzongkha, the national language.
Haa's major feature is the Haa Valley, a steep north-south valley with a narrow floor. The name Haa (pronounced "hah"), as well as the more ancient name Has connotes esoteric hiddenness. An alternative name for the district is "Hidden-Land Rice Valley."
The Haa chhu (river) that flows through the valley stems from Mount Jomolhari.