Wonders of Mongolia

The Trans-Mongolian Railway connects the Trans-Siberian Railway from Ulan Ude in Russia to Erenhot and Beijing in China through the capital Ulaanbaatar. The weekly trans Mongolian train leaves Moscow for Beijing every Wednesday. 7621 km journey takes 6 days until destination. The train crosses Seberia, cuts across Mongolia  and Gobi dessert, then enters China go through great wall. There is second weekly train between Moscow and Ulaanbaatar. There are two trains in a week between Beijing and Ulaanbaatar. Alternatively, there are daily trains between Irkutsk and Ulaanbaatar. Domestic trains: All major towns like Zamyn Uud along the trans- Siberian railway. 

In 2007, only about 2600 km of Mongolia's road network were paved. Another 3900 km are graveled or otherwise improved. This network of paved roads was expanded to 4,800 km in 2013, with 1,800 km completed in 2014 alone.[5] This included the roads from Ulaanbaatar to the Russian and Chinese borders, paved road from Ulaanbaatar to Kharkhorin and Bayankhongor, another going south to Mandalgovi, and a partly parallel road from Lün to Dashinchilen, as well as the road from Darkhan to Bulgan via Erdenet. The vast majority of Mongolia's official road network, some 40,000 km, are simple cross-country tracks.
Construction is underway on an east-west road (the so-called Millennium Road) that incorporates the road from Ulaanbaatar to Arvaikheer and on the extension of the Darkhan-Bulgan road beyond Bulgan. Private bus and minibus companies offer service from Ulaanbaatar to most aimag centers.
In September and December 2014 roads connecting Dalanzadgad town of Ömnögovi Province and Mörön town of Khuvsgul province with capital city of Ulaanbaatar were completed.
Bus are the main mode of public transportation in Ulaanbaatar. There is no set time table, but buses pass stops at approximately 15-minute intervals. Buses runs between 7:00am and 10:00pm. 
There are few licensed taxi companies such as Ulaanbaatar taxi (1900-1991), Noyon taxi (1900-1950), Telecom taxi (1900-1109),1616 taxi (1900-1616) and Taxi  operating in Ulaanbaatar. And there are many drivers with private unlicensed cars who act as taxis.
A typical fare is MNT 800-1000 per kilometer; taxi drivers tend to ask for more especially if the client is a foreign national. However, many unofficial taxis use the "EasyRide" platform to take orders, which is also available in English. Official taxis with proper markings are allowed to drive without plate number restrictions on the first lane of Ulaanbaatar's central road usually reserved for large public transports such as buses and trolleybuses from October 2013.
Chinggis Khaan International Airport outside of Ulaanbaatar is the major airport in Mongolia that offers international flights. There are other airports that have international status such as the ones in Choibalsan and Khovd towns that connect nearby Chinese cities of Ürümqi, Hailar, Erenhot and Manzhouli: They are more popular among the local population.
As of 2013, domestic air carriers such as MIAT Mongolian Airlines, Eznis Airways (unexpectedly suspended its operation on May 22, 2014) Aero Mongolia, Hunnu Air as well as international carriers such as Aeroflot, Korean Air, Air China and Turkish Airlines are offering scheduled services. Domestic airlines except MIAT Mongolian Airlines provide regular service between Ulaanbaatar and aimag centers. 
Ulaanbaatar can be accessed with regular flights from major cities such as Moscow, Berlin, Frankfurt, Beijing, Hong Kong, Singapore, Shanghai,  Seoul, Tokyo, Osaka (served only in summer), Bangkok (discontinued by Hunnu Air), Istanbul and Bishkek. In June 2014, Hunnu Air launched its previously announced flight to Paris but discontinued it shortly after.
In 2013 the first purely air cargo operator was registered at the Civil Aviation Authority of Mongolia and is planned to commence operation in 2014. 
Talks of a possible restart of flights between the Russian city of Ulan-Ude and Ulaanbaatar by a Russian airline have been reported.