The study discusses the processes of reactivation of passenger rail traffic in Poland in the years 2000–2020. After the reductions of the railroad network carried out before 2000, a renaissance of passenger transport could be observed. In the period under study, 63 sections of the railway lines were reconstructed. The total length of the reactivated routes was 1992 km, of which the electrified sections covered 549 km of the network. The largest areas of the concentration of reactivation activities were identified in south-eastern and northern Poland. The average speed on most routes was 65 km/h. The transport offer for 55% of the lines was based on more than six connections per day. Inconsistencies were also identified: out of 63 routes, passenger traffic was suspended again in 20 sections. Three types of reactivated routes can be identified, most of which are blindly terminated routes. The identified processes of reconstruction of traffic systems after 2000 represent yet another phase of railroad operations in Poland, after the previous phase of intensive regression and underfunding.