Wikipedia
Gedrosia (; ) is the Hellenized name of the part of coastal Baluchistan that roughly corresponds to today's Makran. The area which is named Gedrosia, in books about Alexander the Great and his successors, runs from the Indus River to the southern edge of the Strait of Hormuz. It is directly to the south of the countries of Bactria, Arachosia and Drangiana, to the east of the country of Carmania and due west of the Indus River which formed a natural boundary between it and Western India. The native name of Gedrosia might have been Gwadar as there are two towns by that name and a bay ( Gwadar Bay) in central Makran.
The Gedrosians are known to have successfully prevented the Indian Mauryans from capturing the western-most parts of their state.
Following his army's refusal to continue marching east at the Hyphasis River in 326 BC, Alexander the Great crossed the area after sailing south to the coast of the Indian Ocean on his way back to Babylon. Upon reaching the Ocean, Alexander the Great divided his forces in half, sending half back by sea to Susa under the command of Nearchus. The other half of his army was to accompany him on a march through the Gedrosian desert, inland from the ocean. Throughout the 60-day march through the desert, Alexander lost at least 12,000 soldiers, in addition to countless livestock, camp followers, and most of his baggage train. Some historians say he lost three-quarters of his army to the harsh desert conditions along the way. However, this figure was likely based on exaggerated numbers in his forces prior to the march, which were likely in the range of no fewer than 30,000 soldiers.
There are two competing theories for the purpose of Alexander's decision to march through the desert rather than along the more hospitable coast. The first argues that this was an attempt to punish his men for their refusal to continue eastward at the Hyphasis River. The other argues that Alexander was attempting to imitate and succeed in the actions of Cyrus the Great, who had failed to cross the desert. The decision to cross the Gedrosian Desert, whatever his intentions, is regarded as the largest blunder in Alexander's Asiatic campaign.
Gedrosia is a dry, mountainous country along the northwestern shores of the Indian Ocean. It was occupied in the Bronze Age by people who settled in the few oases in the region. Other people settled on the coast and became known in Greek as Ichthyophagoi or 'Fish eaters'.
The country was conquered by the Persian king Cyrus the Great (559-530 BCE), although information about his campaign is comparatively late. The capital of Gedrosia was Pura, which is probably identical to modern Bampûr, forty kilometers west of Irânshahr.
Gedrosia became famous in Europe when the Macedonian king Alexander the Great tried to cross the Gedrosian desert and lost one third of his men.
Several scholars have argued that the Persian satrapy Maka is identical to Gedrosia (which is a Greek name). One argument is the similarity of the name Maka to the modern name Makran, a part of Pakistan and Iran that is situated a bit more to the east. However, it is more likely that Maka is to be sought in modern Oman, which was called Maketa in Antiquity.