structural:summarization
The Trans-Mongolian Railway connects Ulan-Ude on the Trans-Siberian Railway in Buryatia, Russia, with Ulanqab in Inner Mongolia, China, via Ulaanbaatar, the capital of Mongolia. It was completed in 1956, and runs from northwest to southeast with major stations at Naushki/Sükhbaatar on the Russian border, Darkhan, Züünkharaa, Choir, Sainshand, and Zamyn-Üüd/Erenhot on the Chinese border, where the railway changes from single-track to double-track and its gauge changes from 1,520 mm Russian gauge to 1,435 mm standard gauge. The railway also has important branch lines to Erdenet and Baganuur.