Ulaanbaatar has the large market -- can't remember what it's called. It sells everything you will need for a trip into the Gobi. However, be very careful, a number of gangs work the markets to try and mug/steal from backpackers/tourists -- they pulled a knife on the person I was with to cut open his jacket to try and get to his inside pocket.
It was a nice city and the people are soo friendly.
Ulan Bator is the capital of Mongolia. It is not a massively touristy city. However, there are a few museums (the natural history museum, while in bad shape, hosts some fantastic exhibits of dinosaurs found in the Gobi desert), a large temple, and a handful of souvenir shops on the main avenue.
Don't expect gastronomy in Ulan Bator, instead you will find local fast food restaurants with limited selection, and a few Korean restaurants favored by the locals. We learned that the well known dish called "Mongolian beef" is actually an American invention... the local beef is usually dried on the roof of the nomads tents, and is very chewy.
When choosing your hostel in Ulan Bator, make sure you pick one centrally located with good heating and hot showers as nights can be very cold, and many people still live without running water. There is only a limited selection of Ulan Bator hostels and they always supplement their business with organized trips. If possible, try to book your stay in advance, as the supply of Ulan Bator hostel rooms is limited. We also recommend that you try to pick a place which offers train station or airport pick up. The taxi system is almost non-existent, and it's hard to distinguish taxis from regular cars on your own. If you do catch a taxi, you should try to haggle for cost of your trip if you can, as it is the customary thing to do.
Don't choose to visit a hostel in Ulan Bator if you want to party, because the streets are not the safest in the world at night, and it's highly recommended to stay in after dark.
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