Though there are monasteries liberally scattered around UB, my favorite was easily the one just down the street from my guesthouse/ ger camp in Ulan Baatar.
Gandan Monastery
The Ganden Monastery actually reminded me a lot of temples from my trip to Tibet a few summer ago. With all the bright colors and prayer flags of Tibetan Buddhism, Gandan also had the privilege of an active monastic community without as many restraints on their beliefs or actions.
When I made it to the temple, in the middle of a weekend afternoon I found it lively with crowds in traditional clothes or western wedding wear, most of them crowding in to circumambulate the Buddha inside.
The main area leading up to the temple was actually hard to walk through. If not just for the crowds of people, then for the flocks of pigeons that were looking for a handout.
All of the monks I managed to interact with were quite friendly, though.
And of course, the prayer wheels and stupas and other trappings of Tibetan Buddhism were in abundance.
In this corner of Asia so far away from what I typically think of as anywhere near the Tibetan cultural zone, it brought a smile to my face to find such a striking monument to Tibetan Buddhism.