This paper explores the commonly used metaphor of the palimpsest prevalent in urban studies, and suggests that there are realities in the field that are overshadowed by the dominant use of the metaphor. Whilst the palimpsest is a useful metaphor to illustrate chronological superimposition or traces of the past that remain hidden, it is inadequate in describing sites that feature material, spatial and temporal juxtapositions. To remedy this gap, the paper introduces the concept of brecciation, inspired by Sigmund Freud, to provide an alternative means to consider how the accumulation of materials affects planning in the city. Examples from two specific sites in Rome illustrate how brecciation enhances an understanding of the sites and enables to evaluate the practices of urban heritage in recent urban initiatives. By way of conclusion, the paper highlights the benefits of engaging with a concept that reveals concatenations at a site, and suggests that further work on brecciation could be expanded to include the exploration of intangible entanglements. [ABSTRACT FROM AUTHOR]