“This a good site for finding out the latest in rail news in Turkey.
I do have a question on the Metro service and that is; Is the PENDIK METRO station open or is the line still under construction? The reason for asking is that some web sites differ in where you alight/get off the train for the PENDIK MAIN Station for trains to Ankara and beyond.”
The Pendik station of metro and trains are different, 1 km away from each other. There’s a plan to extend metro to HST station. Until that time, you can walk or get a minibus which runs very frequently between metro and HST station. For the time being, only HSTs to Ankara and Konya departs from Pendik.
Detailed information about how to get to Pendik Station from many points in Istanbul, click station link.
And many thanks for your kind words.