There’s only very few trains running between Turkey and other countries. Balkan trains towards west and Iran train towards east. Soon, train to Georgia/Azerbaijan is expected to start as well.
In last 10 years, Turkey has focused on high speed trains. They become very popular. Currently they are running on 4 routes. Soon 2 new routes will be added.
Though they are slow and become less and less in Turkey and whole world, long distance trains offer a very comfortable and pleasent way of travel especially with sleepers, couchettes and dining cars.
In many short distance routes, trains are the first choice of passengers. Service is given mainly by multiple units (DMU/EMU) where loco+coaches may also be seen.
Suburban trains are running in three metropols of Turkey: Istanbul, Izmir and Ankara. All three infrastructures and sets are renewed recently and are the backbones of public transportation.
In some strechs where passenger trains run once, there’s no currently service due to renewal works or other reasons.