(This article is about the Spanish city. There is also a place named Cadiz in the U.S. state of Ohio.)
The city was originally founded as Gadir (meaning walled city) by the Phoenicians, who used it in their trade with Tartessos. Traditionally, its date of establishment is circa 1100 BCE, although upto now no finds have been found yet that date back further than the 9th century BCE.
Via the Carthaginians it fell in hands of the Romans, who called it Gades. Gadir became an important commercial city during the Carthaginian domination and disappeared in the last days of the Roman Empire when commerce decayed.