Trarza (Arabic: ولاية الترارزة, romanized: Wilāyat al-Tarārizah) is a region in southwest Mauritania.

Trarza borders the regions of Inchiri and Adrar to the north, Brakna to the east, and the country of Senegal to the south.

Its western coastline on the Atlantic Ocean is interrupted only by the Mauritanian capital Nouakchott, which the region completely surrounds.

[9] Trarza borders the regions of Inchiri and Adrar to the north, Brakna to the east, and the country of Senegal to the south.

Its western coastline on the Atlantic Ocean is interrupted only by the Mauritanian capital Nouakchott, which the region completely surrounds.

Mauritania is mostly covered with desert, with only its western regions around the coast of the Atlantic Ocean having some vegetation.

Research has indicated that the Saharan movement has resulted in reduction of rains in the region from the 1960s, when it received close to 250 mm (9.8 in) of rainfall.

[11] Trarza is divided into six departments, namely, Boutilimit, Keur Massene, Mederdra, Ouad Naga, R'Kiz and Rosso.

The local governments have their own legal jurisdiction, financial autonomy, an annual budget, staff, and an office.