Maximum pebble size (a_max) as a function of the radial distance after 2 × 10⁵ yr of evolution obtained in our fiducial run. In the outer part of the disk, this size is limited by the radial drift (a_drift<a_frag), while in the inner part of the disk, it is limited by fragmentation. Aggregates that are large enough to participate in planetesimal formation via streaming instability (St > 10^-2, purple solid line) are only present outside of the snow line. Inside of the snow line, the aggregate size corresponds to St <α_v/ 2 (gray solid line), which means that their transport is dominated by viscosity rather than radial drift.