A distant western seaport — the far edge of the known world, and the OPPOSITE direction from Nineveh, which is the whole point of Jonah's choosing it. ⚠ Most likely TARTESSOS in southern Spain (the Guadalquivir region of Andalusia), a wealthy Phoenician metal-trading colony famous for silver, tin and lead — Ezekiel 27:12 has Tarshish trading exactly those metals to Tyre, and 'ships of Tarshish' become a byword for great ocean-going merchantmen (1 Kings 10:22). Other proposals put it at Tarsus in Cilicia or on Sardinia (a Phoenician inscription there names 'Tarshish'). Whatever the exact harbour, the sense is 'as far west as a ship can carry me' — Jonah, told to go east to Assyria, buys passage to the western end of the sea. The Douay, from the Vulgate, spells it Tharsis.