SignificanceUncovering the constitutive coherent structure in the inner layer of the canonical turbulent boundary layer has remained a central fluid mechanics theme, because it tests our intellectual ability to understand even the simplest external flow. We describe here how turbulent spots are initiated in bypass boundary-layer transition and uncover the ubiquity of concentrations of vortices in the fully turbulent region with characteristics remarkably like transitional–turbulent spots. We present strong evidence that these concentrations of vortices are the constitutive coherent structure of the inner layer near the wall. This study contributes to the unification of understanding of phenomena occurring in boundary-layer late-stage transition with near-wall turbulent boundary-layer structure and dynamics in the developed flow.