Architectural projects of the second half of the 1920s - early 1930s reflect the avant-garde period of the development of Soviet architecture. Our museum has the most studied and probably the richest collection of architectural graphics of the Leningrad avant-garde. The same period (and partly the previous one) includes a group of materials created by the employees of the Otkomkhoz of Lensovet directly for the expositions in our museum. These objects reflect not only the history of the city and the graphics of the avant-garde era, but also that period in the history of our museum, when it served as one of the first centers in the world for the comprehensive study and design of the urban structure and environment, what we now call “urban studies”.