I am the official currency of a country known for its unique blend of European and Asian cultures. The country I belong to is located on the crossroads of two continents. My banknotes often depict iconic landmarks of my nation as well as famous cultural figures. The value of my currency is influenced by the price of oil and gas exports.

1. My nation's capital is a city that straddles the Bosphorus Strait.
2. I am used in a country that was once the heart of a vast empire.
3. My value has experienced significant fluctuations in recent years.
4. My country is a member of the G20.