Invited lecture at the 5th Research Synthesis Forum 2022 organized by the Association of Mongolian Doctors in Japan (co-sponsored by the Embassy of Mongolia in Japan).  After reviewing and understanding the transition in Ulaanbaatar (former Urga) from the end of the 19th century to the present day through historical documents and photographs, I gave a lecture on the results of my research on the two forms of settlement seen in Ulaanbaatar today (1: low-rise housing in ger areas, 2: apartment housing in the central area where urban planning was done during the socialist era).