Ulan-Ude sits on the Trans-Siberian and Trans-Mongolian railways, which makes the train the classic way in. From Moscow it is about three full days and nights; from Irkutsk a short overnight; from Ulaanbaatar around 24 hours; from Beijing roughly two and a half days.
Baikal International Airport (UUD), about 12 km west of the city, has daily flights from Moscow and Irkutsk and seasonal connections to a handful of Russian cities and Mongolia. The drive into town takes about 30 minutes.
By road, the M55 highway runs west to Irkutsk (about 7 hours) and east to Chita; the Kyakhta highway runs south to the Mongolian border. Long-distance marshrutkas link the major Buryatian towns.