Arachosia // is the Hellenized name of an ancient satrapy in the eastern part of the Achaemenid, Seleucid, Parthian, Greco-Bactrian, and Indo-Scythian empires. Arachosia was centred on the Arghandab valley in modern-day southern Afghanistan, although its influence extended east to as far as the Indus River in modern day Pakistan. The main river of Arachosia was called Arachōtós, now known as the Arghandab River, a tributary of the Helmand River. The Greek term "Arachosia" corresponds to the Aryan land of Harauti which was around modern-day Helmand. The Arachosian capital or metropolis was called Alexandria Arachosia or Alexandropolis and lay in what is today Kandahar in Afghanistan. Arachosia was a part of the region of ancient Ariana.