The Great Kanto Earthquake and Second World War Fire Bombings have left contemporary Tokyo with almost no monu-ments from the past. One of the areas that has been spared in both destructions is Yanesen, part of the three neighbour-hoods Yanaka, Nezu, and Sendagi located in northeast central Tokyo. Nezu has a peculiar urban character that persists despite the lack of conservation and constant change in its built environment. Its unique character is defined by a sense of local, domestic, and neighbourhood closeness and is linked to the traditional identity of Shitamachi. This article hypothe-sizes that the main element that preserves the character of Shitamachi in Nezu is based on the relationships rather than on objects that need to be preserved. The analysis focuses on the relationships between public and private spaces and captures changes in the built environment in Nezu over six years. The comparative analysis applied mapping and a photo-graphic survey of the public‐private interface. The results showed how the persistence of the urban character is supported by a dynamic change in the built environment which functions as a complex system. The relationships between elements of the built environment are demonstrating non‐linear causality at the public‐private interface and contribute to Nezu’s enduring character.