The Red Army entered Poland, crossing its pre-1939 border, on a freezing cold night of 3/4 January 1944 near Rokitno, east of Sarny. In six months the frontline reached the Vistula where it stopped for more than 5 months. The Russian offensive in January 1945 saved the railway network in Upper Silesia and part of the lines in Lower Silesia from destruction. The army was followed by “trophy brigades” coordinated by the Red Army Wartime Trophy Board, which dismantled and carried away elements of infrastructure, steel structures and rolling stock, at the same time devastating the buildings. This was a common practice, in particular in areas which under the Treaty of Yalta were to be incorporated into the Polish state, that is, lands in the north-east, the Lubusz Lakeland, West Pomerania, and Lower Silesia.
The Russians dismantled more than 1,554 miles (2,500 km) of normal-gauge lines (932 miles, i.e. 1,500 km were not reconstructed) and 205 miles (330 km) of narrow-gauge lines (124 miles, i.e. 200 km were not reconstructed), and 1,554 miles (2,500 km) of second tracks (mostly in Lower Silesia). Also, nearly the whole traction network on a section of 249 miles (400 km) was stolen in Lower Silesia. In July 1945, in 3 weeks the Russians carried away the rolling stock, dismantled the networks, substation and power station equipment and destroyed part of the poles. Polish State Railways could only remove the remaining cables and use them for the needs of the Warsaw railway junction.
Also, the Tarnów – Szczucin line in Lesser Poland was dismantled. The longest section of the second track (188 miles, i.e. 302 km) was dismantled on the state border line – Skandawa – Korsze – Ełk – Białystok – Czeremcha. To enable transport of supplies the Soviets converted some railway lines into broad-gauge. Among other lines, these included: Kraków – Trzebinia – Katowice, Katowice – Ligota, Katowice – Gliwice – Kędzierzyn-Koźle – Prudnik, Chorzów – Batory – Bytom – Pyskowice – Opole Wschodnie, Jelcz – Wrocław, Skawina – Oświęcim – Czechowice – Ostrawa, Częstochowa – Lubliniec – Kluczbork – Ostrów Wielkopolski – Leszno – Głogów – Żagań, Hrodna – Warsaw, Volkovysk – Czeremcha – Siedlce – Warsaw, Brest – Łuków – Dęblin, Dorohusk – Chełm – Lublin, and Rava-Ruska – Przeworsk.
In addition, broad-gauge was also applied on trunk lines: Königsberg – Tczew – Gdańsk – Chojnice – Szczecin, Iława – Toruń – Poznań – Frankfurt on the Oder, Białystok – Warsaw – Poznań, Warsaw – Częstochowa – Opole – Wrocław – Bolesławiec, Mysłowice – Katowice – Chorzów – Bytom – Pyskowice – Opole,and Przemyśl – Kraków – Katowice – Łódź – Krotoszyn – Leszno – Żagan. Broad-gauge lines in Silesia, leading straight to collieries, facilitated the transportation of coal to the USSR and they remained in operation until 1947. The first train carrying a load of coal to Warsaw departed from Silesia on 7 February 1945.
In connection with the demarcation of new borders of Poland, many lines lost their significance, in particular lines in the territory of East Prussia, leading to Königsberg. Polish State Railways (PKP) reconstructed part of those lines. e.g. near Ełk: Ełk – Pisz – Ruciane-Nida – Szczytno – Wielbark, Ełk – Olecko, Ełk – Orzysz – Mrągowo, Ełk – Prostki, Malbork – Kwidzyn, and Kętrzyn – Węgorzewo.
PKP took over railway lines from the Soviet Central Military Transportation Management under agreements signed on 11 July (in the Regained Territories) and on 15 August 1945 (the rest of the railway network). The damaged bridges and viaducts on main lines were temporarily reconstructed by Red Army sappers. Similarly, railway lines were restored to operation at a speed of 6 – 16 miles (10 – 25 km) a day. Fixed railway bridges, replacing wooden temporary structures, were built up until the early 1960s.
In summer 1944 in Poland, in the area of Lublin, 208 steam locomotives (including 30 actives ones), 300 passenger carriages (including 100 operable ones) and 2,583 freight wagons (2,000 operable ones) were found. Some lines were left there as normal-gauge lines, among other reasons, due to the transport of crude oil from the mines in the Subcarpathian area. The damaged sections of tracks were repaired by inserting various types of rails stripped from railway station tracks or from second tracks on double-track lines. 12 transfer points from broad- onto normal-gauge wagons were arranged.
The foundations of the Ministry of Railways were formed by the Department of Transport, Post Offices and Telegraphs, initially based in Chełm Lubelski. On 1 August 1944 the “Lublin Government” issued a decree calling former railway workers in the territories freed from German occupation to work, and in November the railway was “militarised” and the workers were transferred under the control of military criminal law authorities. Such a state of affairs continued until 1949. The Railroad Guard Service was appointed and new railway directorates were formed in Lublin, Gdańsk, Olsztyn, Wrocław, and Szczecin, and the ones existing before the war in Kraków, Poznań, Warsaw and Katowice were reactivated. In April 1945, the Railway Directorate in Poznań convened the first meeting of the Commission for the Determination of Names of Railway Stations in the Regained Territories. In one month the commission gave names to all railway stations in the territories incorporated into Poland.
Passenger transports were put into operation. People were often carried by freight wagons and due to overcrowding – they also travelled on the roofs and steps of the wagons. Freight trains, apart from supplies for the army, also carried supplies for cities, including: coal, wood, foodstuffs, and kerosene. Interestingly, in Lower Silesia German railway staff worked until 1946.