So comfortable railway station.
A great entrance into Mongolia
The capital ailway station
Nice train station
It's really old and smells badly
Old russian and communist style train station. No security check, people can walk around the station and platform freely. There are not much English notice and sign. People there were not good in English too. Beggars around train stations and restaurant.
You can buy really cheap train ticket (hard seat for 12 000 MNT) to get to Zamiin-Uud (close to the Chinese border).
There is almost no queue (at least during week days at the end of September) to buy train tickets and the ticket number system (for queuing) is quite efficient.
It is also possible to buy bus tickets (which avoid the journey to the bus stations). For this, be careful as the ticket office dedicated to bus closes at 5pm30.
Amazing train station, in 1991