Day in the life of a Turkish fishmonger
11 July 2012 Last updated at 11:35 BST
In recent years, Turkey's fish production has increased to almost 600,000 tonnes a year.
Alongside the container ships on the Bosphorus, fishmongers sell everything from swordfish to sardines.
Howard Johnson spent the day with fishmonger Hasan Kayhan to find out just how he makes a living.