The allocation of cities for the Levite tribe commenced with the descendants of Aaron, who were part of the broader Kohathite family [מצודת דוד]. A natural question arises regarding why Aaron's descendants were granted their portion prior to the rest of their fellow Levites.
One perspective suggests that their elevated and honorable status as priests earned them the privilege to cast the lot and secure their cities before anyone else [ביאור שטיינזלץ]. Conversely, another approach dismisses any connection to their priestly rank. According to this view, there was no deliberate preference based on their status; they received their cities at this specific moment simply because their lot happened to be drawn first [מצודת דוד].