The passenger services/routes that are effected due to renewal works etc are as follows (as of March 2021):
All international and main line train services are suspended due to Covid-19.
All high speed train and most of the regional train services are in operation.
Samsun-Kalin railway is commissioned after kept closed for 5 years, yet only for freight trains. Passenger train services have not started yet due to Covid-19.
After several years, Transasia started in 2019 between Ankara and Tehran. It’s expected to start right after Covid-19.
Gaziantep and further rail connection to Mardin, Nusaybin and Syria are closed for all train traffic. Track are being renewed in Gaziantep for Gaziray suburban train project.