Set between mountains, steppe, and extreme seasons, Ulaanbaatar, the capital of Mongolia, is a city shaped by a long transition from nomadic mobility to permanent urban settlement. Once a mobile monastic centre and today a metropolis of 1.6¿million people, the city has transformed rapidly: historical temples, socialist masterplans, prefabricated khoroolol districts, and speculative high¿rises coexist in a fragmented urban landscape. Many landmarks have disappeared, while others remain overlooked in the city's vast 4,700¿square-metre territory. This guide offers a comprehensive overview of Ulaanbaatar's architectural development - from pre¿socialist origins to state¿building Neoclassicism, socialist Modernism, and post¿1990 construction booms. More than 130 buildings and sites are presented through photographs, maps, typological analyses, and contributions by local researchers. Written by an author rooted in both Germany and Mongolia, the guide combines an insider's understanding of Ulaanbaatar with the distance needed for critical analysis, highlighting the tensions between heritage and demolition, planning and speculation, and movement and permanence as the city searches for a coherent architectural identity.