Istanbul history

Istanbul has a very long history.  It was originally a small settlement dating back to 600 BC called Byzantine.  When the Roman emperor Constantine transformed the city into a major metropolis it was renamed after him (Constantinople) and was the capital of the Byzantine Empire (the eastern part of the Roman Empire).  It eventually outlasted the Roman Empire.  It is located strategically at the mouth of the Bosporus Straights that lead out of the Black Sea and into the Mediterranean Sea.