'Behind the Iron Gate' is the name of the massive-scale housing estate in the centre of Warsaw, consisting of 19 apartment blocks, 16 storeys each, designed by a team of Polish architects (Jan Furman, Jerzy Czyz, Jerzy Józefowicz, Andrzej Skopinski) between 1966-1970. This realisation has been interpreted as one of the far-reaching consequences of the Athens Charter which commited CIAM to a single type of urban housing, described as high, widely-spaced apartment blocks wherever the necessity of housing high density of population exists. In the 1970s, the Behind the Iron Gate housing estate was considered a symbol of Polish socialist prosperity. The principles of so-called modern rationalism - that is, 'Siedlungen' responding to the drastic housing shortage, and 'Existenzminimum' understood as the apartment for the minimal existence - became subject to a political propaganda which affected the post-war urbanism in Poland as the country behind the Iron Curtain. Since 1989, the Behind the Iron Gate area is one of the most active construction sites in the city, attracting foreign investments, and gradually shaped as a 'Warsaw Manhattan'. Former green zones and playgrounds now host parking lots, bank and insurance company buildings, business centers, and exclusive hotels. At the same time, the Behind the Iron Gate housing estate is a rather neglected part of the city; the pre-fabricated apartment blocks are often referred to as 'architecture on pension', 'slums' or even 'pathological substandards'. 'A Surplus of Memory' is the title of memoirs by Yitzhak 'Antek' Zuckerman, a member of the Jewish Fighting Organization Command, who took part in the Warsaw Ghetto Uprising. The Behind the Iron Gate housing estate was designed upon the field of ruins of the so-called 'small ghetto' liquidated in August 1942. On today's map of Warsaw, there are only few ruins in this highly built-up area that constitute the Jewish Route of Memory: a part of the ghetto wall, a gate, fragments of the original pavement and rails, and some pre-war 'memory places', such as the sites of non existing houses: of Isaac Bashevis Singer at Krochmalna street and of Icchok Lejbusz Perec at Ceglana (now Pereca street). Designed as a narrative walk along the contemporary streets and squares of the Behind the Iron Gate area, the paper examines the specificity of urban memory and questions the notion itself. Paul Ricoeur's description of the threefold, interpretative nature of the historiographical operation (as demonstrated in his 'Memory, History, Forgetting') is referred to the concrete urban site with its ambiguous character. Acknowledging the reciprocity of writing history and collecting memories, as well as the difference between the ontological question and the 'hauntological' description, the paper discusses the possibilities of historiographical and commemorative tasks of architecture. The Behind the Iron Gate area with its contemporary in-fills, socialist blocks and ruins, where architecture is not turned into a timeless monument or a museum-district, serves as an example of both the space of memory and the space of forgetting.