Irkutsk and Ulaanbaatar are connected by the Trans-Mongolian railway, but there
are not many trains that travel on it. The most popular and reliable
train is the daily train 364. It departs Irkutsk in the evening and
arrives to Ulaanbaatar early in the morning after 2 nights of travel. This train
does not have 1st class cabins, but it is possible to book (min. 2 people
required) the whole entire 2nd class cabin if you want space and privacy.
Train 364 Irkutsk - Ulaanbaatar (daily in high season)