Grand Erg Oriental follow the wind's direction. There are other types of dunes, as well as "complex" dunes. Saharan winds are also known to clear an area of sand altogether, leaving bare rock (hamada) or gravel (reg). The "Grand Erg Oriental" is accessible overland by an Algerian road, which goes south from Constantine. It passes through the Aurès mountains, then salt lakes by the city of Biskra. Next the road skirts the western edge of the erg. After about 500 km. in all, it reaches the ancient oasis of Ourgla [Wargla]. Since late antiquity Wargla was a stop for the Saharan trade, being
Erg (tug) Halifax Harbour and is the greatest loss of life in regards to a shipwreck within these waters. Upon inspection, it was decided that "Erg" was beyond repair and on August 24, 1943, she was taken to her final resting place and sunk for the third and final time. The "Erg" shipwreck site was rediscovered in 2001 in the northern part of the Bedford Basin (near Roach Cove) by the Nova Scotia Exploration Society. The site is a protected heritage site and is visited by many divers. Objects which were recovered from "Erg", such as the ships' whistle and portholes are