 The city is served by Dushanbe International Airport which, as of April 2015, had regularly scheduled flights to major cities in Russia, Central Asia, Delhi, Dubai, Frankfurt, Istanbul, Kabul, and Ürümqi amongst others.Tajikistan's principal railways are in the southern region and connect Dushanbe with the industrial areas of the Gissar and Vakhsh valleys and with Uzbekistan, Turkmenistan, Kazakhstan and Russia.The Dushanbe trolleybus system operates public buses in the city, and construction of a metro system is due to begin in 2025.