The presence of multiscale interactions means that the complex urban wavefield must be observed and analyzed in order to understand seismic ground motion in urban environments. Originally called site–city interaction, the interactions between soil and structures, structures and soil, and between structures contribute to the modification of urban seismic ground motion. This may affect the lateral variability of the ground motion observed in relation to earthquake damage, the characterization of site effects in urban areas, and also the response of civil engineering structures designed without consideration of the immediate urban environment. The METACity‐Quito experiment was designed to take accurate measurements of the effects of the resonator array formed by structures in the seismic wavefield, in the manner of an urban metamaterial. Current applications in the fields of physics, acoustics and, more recently, geophysics have shown the existence of forbidden bands, that is, frequencies at which seismic energy vanishes. This concept could help to understand the heterogeneous distribution of damage in urban areas as well as to imagine the future design of seismic‐proof cities.