Destinations in Northern and Western Georgia (including minibuses to Russia, through Kazbegi) are served. It's rather disorganised and sprawling, but you'll find minibuses to almost anywhere.
Buses to Russia
To Rostov-on-Don: There is a bus from Yerevan to Rostov-on-Don, stopping in Tbilisi along the way.
To Valdikavkaz: 4hrs, daily, 40 GEL.
From Vladikavkaz: Buses depart from the Osetinsky Theatre at 09:00 (600 RUB).
To Batumi (6 hrs, 20 GEL, hourly 08:00-20:00).
From Batumi - see Batumi Bus Terminal.
To Kutaisi (4 hrs, 10 GEL, hourly 07:00-19:00).
From Kutaisi - see Kutaisi Bus Station.
To Stepantsminda (2 hrs 45 min, 10 GEL, hourly 08:00-19:00).
From Stepantsminda - see Stepantsminda Bus Station.
To Mtskheta (25 mins, 1 GEL, every 15 min 07:30-20:30).
From Mtskheta - see Mskheta bus stop.
To Akhaltsikhe (4 hrs, 8 GEL, hourly 08:00-19:00).
From Akhaltsikhe - see Akhaltsikhe Bus Station.
To Borjomi (3 hrs, 6 GEL, hourly 08:00-19:00).
From Borjomi - see Borjomi Bus Station.
To Gori (1 hr, 3 GEL, every 15 mins 07:00-19:30).
From Gori - see Gori Bus Terminal.
To Zugdidi (5.5 hrs, 15 GEL, hourly 08:00-20:00).
* Prices and schedule as of June 2016.
Next to Didube metro station. There are no signs in English. Alternatively buses № 21 and № 46 go there from the city center, and № 150 from the Ortachala station.