Sand Dunes near Merzouga (Morocco). Merzouga is a small village in southeastern Morocco, 35 km from Rissani, 55 km from Erfoud, and 50 km from the Algerian border. The village is known for its proximity to Erg Chebbi, a Saharan erg. Merzouga has the largest natural underground body of water in Morocco. In 2006, it experienced devastating flash floods, displacing 1,200 and resulting in some deaths.