Tashkent was the capital city of Uzbekistan in 2008. (AUDIO: Brave New Town) It was east of the Caspian Sea and had a mountain range to its west. The city was separated into the old town - in the east - and the new town - in the west.
The Second Doctor, Zoe Heriot, and Jamie McCrimmon visited the city in August 1919, during the takeover by the Soviet Union. (AUDIO: The Memory Cheats)