Zabaykalsk is the final stop on the Russian side of the Russia-China border on the Trans-Manchurian route from Moscow to Beijing. Trains from Russian stations, Irkutsk, Ulan Ude and Chita stop regularly at Zabaykalsk with a weekly service from Chinese stations, Manzhouli, Harbin and Beijing. The service from Irkutsk decouples from a Irkutsk-Kharbarosk at Chita waiting six hours before coupling with the Chita-Zabaykalsk service. It is possible to look around Chita during this break or stay on the carriage in the shunting yards. Toilets are closed for the full 6 hours with the station a 15 min walk away.
The route Chita-Zabaykalsk is serviced daily. If you get off in Zabaykalsk, you need to take a bus to cross the border to Manzhouli but you have to buy the train ticket at Manzhouli at the spot (no pre-booking service).
This website can be used to check train schedules.
The bus station is located 800 m from the train station. After leaving the train, head along the platform in the direction from which the train came. Take the footbridge out of the station then follow the station fence in the direction the train was heading (ie China). Look out for the flashing lights on the giant welcome gate.
Expect no one in Zabaykalsk bus station or officials on either side of this border to speak English.
Several busses run daily between Zabaykalsk and Manzhouli, China. The last bus from Zabaykalsk bus station (located near the train station) leaves 15:10 so it might be a good idea to arrive there earlier as Zabaykalsk is probably not a place where you are interested to stay overnight.
Busses arrive at the city centre of Manzhouli.
Bus tickets for this route are 300 rubles plus 100 rubles for baggage. An additional fee of 200 rubles is paid on the Chinese side of the border.
By foot or bicycle
Zabaykalsk is 10 km from Manzhouli, and the road is quite calm with nice wide shoulders. However, as of December 2013, crossing the border by foot or bicycle was not allowed by the Chinese border guards: you have to go in a motor vehicle, bus or take the non-daily train across the border.
Zabaykalsk is almost more a village than a city. The main reason you are here is probably because you are either going to cross a border to China or you've come from China to Russia.
There most likely isn't much to do for a tourist here.