The D 1/2 was a pair of express trains of the Prussian State Railways , later the Deutsche Reichsbahn , which ran between 1895 and 1945. His route led from the imperial capital Berlin over the Eastern Railway to the end of the First World War to Königsberg i. Pr. And Insterburg in East Prussia , coaches continued to run up to the then German-Russian border at Eydtkuhnen or Wirballen . Between the First and Second World War, the train ran to Eydtkuhnen and continued through coachesKaunas to Riga . In the direction of East Prussia the train was number D 1, the counter train in the direction of Berlin was designated D 2. The trains used as day trains carried 1st to 3rd class seating cars and a dining car , while sleeping cars were only used as through cars on the train.
Since 1855, a "Train No. 1" and the corresponding counter train have been running on the Prussian Eastern Railway . This was just one of three pairs of trains that ran the route every day, but not yet an express train. In 1873, the "Courierzug 1" was introduced, the direct predecessor of the D 1. In Berlin, the trains began and ended initially in what was then the Ostbahnhof, north of what is now called Berlin Ostbahnhof (then Frankfurter Bahnhof ). In Koenigsberg the train went to Koenigsberg Ostbahnhof . For the route to Eydtkuhnen, the courier train 1 required 16 hours, 18 minutes according to the schedule.
With the commissioning of the Berlin Stadtbahn in 1882, the old Berlin Ostbahnhof was given up and the "Courierzug 1" began at Charlottenburg station . The train was serviced and made available at Grunewald station .
The D 1/2
From 1895 through coaches were available and the pair of trains was renamed D 1/2. The pair of trains had a different stop concept depending on the timetable year. But the train always ran in the morning from Berlin to East Prussia, where it arrived in the evening, analogously in the opposite direction. In 1905 the train served a comparatively large number of stops. In Berlin, the D 1 stopped at the stations Zoologischer Garten , Bahnhof Berlin Friedrichstrasse and Schlesischer Bahnhof, except in Charlottenburg . Then he drove with stops in Küstrin , Landsberg an der Warthe , Friedeberg (Neumark) , Driesen-Vordamm and Kreuz (Ostbahn)to Schneidemühl , where a locomotive was changed . The train stopped in Flatow (Westpr) , Konitz , Czersk and Preussisch Stargard until the next locomotive change in Dirschau , where a through car to Danzig (in summer to Sopot ) was also handed in . The D 1 then continued to Königsberg with stops in Marienburg , Elbing , Schlobitten and Braunsberg . Its lines on the other side of Königsberg ran over Tapiau and Wehlau (Ostpr)to Insterburg . The train ended here, but there were through cars that continued to the German-Russian border. The end of the train from Berlin was the Russian border station Wirballen (today Kybartai ), where there was a connection to the trains to Russia on broad gauge tracks . In the opposite direction, the German border station Eydtkuhnen was used to change between Russian and German trains. The carrier train of the through cars between Insterburg and the Russian border was the D 55/54, which also ran to and from Berlin, but took the route via Frankfurt (Oder) , Posen and Allenstein .
The D 1/2 through car also went to Memel (today: Klaipėda). In the following years, the Prussian State Railways accelerated the pair of trains considerably; in 1914, with the exception of Schneidemühl, all intermediate stops between Berlin and Dirschau were canceled.
For the route to Insterburg, the D 1 1914 took exactly 10 hours from Berlin Schlesisches Bahnhof, the through car to Eydtkuhnen took 11 hours and 18 minutes.  In the opposite direction of D 2 between Insterburg and Silesian Station needed 15 more minutes. Nine years earlier, the train between Berlin and Insterburg had taken 11 hours and 27 minutes.  The fastest train on the route, however, was the Nord-Express , which covered the 742 km between Schlesisches Bahnhof and Eydtkuhnen in 9 hours and 32 minutes.
In the second half of the First World War , German troops occupied the Baltic States . For military reasons, they switched the track network from Russian broad gauge to standard gauge . Now the train ran through to Vilna at times . The route to Vilnius took him 19 hours, 42 minutes as scheduled.
After the First World War, 123 kilometers of the Eastern Railway to East Prussia, which has now become an exclave , ran over Polish territory. The D 1/2 became part of the corridor traffic and a pair of trains of the privileged rail traffic . The privileged through traffic was operated by the Polish State Railways (PKP) at the expense of the German railways, but initially nobody was allowed to get on or off on Polish territory. Passengers on the trains do not need a Polish transit visa for this . The corresponding contracts were not concluded until 1921, but traffic resumed as early as autumn 1919.
After the First World War, the Baltic states became independent, the railway lines there kept the European standard gauge. From 1920, the D 1/2 through car, which was now extended to Eydtkuhnen as a border station to Lithuania, ran via Kaunas to and from Riga . From 1927 further circulating as a daytime train train pair also encouraged sleeper of CIWL in relation Paris - Riga that from since its reintroduction after the war Warsaw trains running north-Expresswere taken over at the Silesian train station or handed over to them there. In 1928 the train needed 11 hours, 42 minutes for the route from the Schlesisches Bahnhof in Berlin to Eydtkuhnen and another 9 hours and 26 minutes for the journey to Riga. In Eydtkuhnen, where the Mitropa dining car and the rest of the cars remained, the Lithuanian State Railroad took over the through cars to Riga and - after providing a CIWL dining car in the neighboring Lithuanian border station Virbalis - ran them as express train 11/12 via the Lithuanian capital Kaunas to Transition to Latvia near Joniškis . There, the Latvian State Railways took over the train run under the new number 15/16 for the remaining short section to Riga.
From 1929 the pair of trains ran via the then newly opened Königsberg main station . The transit traffic through Poland suffered again and again from the friction between Poland and the German Reich, since the latter since the conclusion of the Versailles Treatysought a revision of the eastern border with Poland established therein. In 1936, outstanding German payments for transit traffic resulted in Poland ending almost all transit services from February 7th. D 1 and 2, along with two other pairs of trains, were excluded from this, as they carried international through coaches and Poland tried to avoid international entanglements. In addition, the pair of trains was now also used for changing traffic with Poland, unlike most other East Prussian trains, passengers could get on and off at the Polish border stations at Chojnice and Tczew .  In 1934, the D 1 required 10 hours, 23 minutes for the route from the Schlesisches Bahnhof to Eydtkuhnen. 
In the summer timetable of 1939, the through car race between Berlin and Riga was the fastest long-term international connection with all three car classes in Europe, despite four borders to be crossed with an average speed of over 76 km / h. Only a few international CIWL pullman suits , for example between Paris and Amsterdam, the Rheingold , which is also subject to higher tariffs, or a few through car runs in FD trains achieved higher average speeds. 
When the Second World War broke out, the Polish army blew up the Vistula bridge near Dirschau. As soon as this was passable again from October 18, 1939, the D 1/2 also ran again, in 1940 even in 15 hours, 6 minutes to Vilna, before the Soviet railway switched the lines in the areas occupied by the Soviet Union to broad gauge. The pair of trains then ran back to Eydtkuhnen, had a through car to Danzig as before and took 11 hours 46 minutes between Charlottenburg and Eydtkuhnen. When the war situation for the German Reich worsened, the pair of trains initially lost the course and dining cars. When in the fall of 1944 the Red Armyinvaded East Prussia, the train route was withdrawn first to Insterburg, then to Königsberg. In mid-January 1945, German rail traffic in East Prussia finally came to a standstill.
As early as 1852, the Ostbahn procured the first locomotives known as "high-speed runners", including type 1A1 locomotives from Borsig , which were used until 1883. The procurement of type 1B locomotives began in 1869, and both types were used in front of the courier trains from 1873. From 1880 onwards, the Ostbahn management in Bromberg no longer procured the locomotives; this task has since been carried out centrally for the state railway directorates . Before the Courier train, the old Ostbahn designs were only supplanted by the S 1 from 1891 , also type 1B locomotives. As early as 1893, the new S 3s were used, which were initially considered the ideal express locomotives. However, these type 2'B locomotives soon proved to be inadequate for the heavier trains, even if a total of 202 locomotives were in service in the Bromberg, Danzig, Posen and Königsberg offices in 1906. From 1905 the more powerful S 5 2 took over their duties, from 1907 supported by the S 6 , also a 2'B tender locomotive. The PKP 1920 took over 81 locomotives from the S 6 as the Pd5 series and used them in front of all corridor trains. For a short time, Prussian S 7s were also used, which for the first time ran between Berlin and Schneidemühl without changing locomotives .
With the acquisition of the S 10 , these 2'C locomotives became the standard locomotives of the D 1/2 for almost two decades from 1914 onwards. They made it possible to cover the Berlin-Königsberg section with just one locomotive change in Schneidemühl. However, the corridor traffic meant that only Polish locomotives were used between Chojnice (Konitz) and Marienburg. The PKP soon replaced the older Pd5 with S 10, which it had taken over as the Pk2 series and stationed in Chojnice. Until then, the S 10, now classified as DR class 17.10, ran through.  The class 17.10 was only gradually replaced on the German sections from 1931 by standard locomotives , initially the DR class 03 , from 1936 the DR class 01. From 1933, the PKP also started using new and powerful locomotives on its section with the PKP Pt31 series , thus invalidating allegations that it was neglecting transit traffic.  This locomotive service remained largely unchanged until 1939. Various express locomotives were used during the war, including the Polish Pt31, appropriated by the DR as class 19.1.
East of Eydtkuhnen, the Lithuanian State Railroad Lietuvos Gelezinkeliai (LG) started using the six earlier Prussian S 10s, which it had taken over and referred to as the Gr10 series, from 1920. Former Prussian P 8s , referred to as K8 by the LG , also drove as a substitute . From 1939 the new Pacifics of the LG Gp series were used for a short time . 
Other trains with the same name
The pair of trains is not to be confused with other earlier express trains with the same train numbers, such as the D 1/2 on the Basel - Frankfurt am Main Hauptbahnhof - Berlin Anhalter Bahnhof route and the D 1/2 from Cologne Hauptbahnhof via Hanover Hauptbahnhof to Berlin Stadtbahn .
- Peter Bock: D 1 Berlin - Königsberg. In transit through Gdansk and through the "Polish Corridor" . EK-Verlag, Freiburg 2012. ISBN 978-3-88255-737-4
- Siegfried Bufe, Bernhard Schülein: Königsberg Express . Bufe-Fachbuch-Verlag, Egglham 2002, ISBN 3-922138-77-2
- Siegfried Bufe: Shifted borders. Memories of the D 1 Berlin - East Prussia - Baltic States . In: EisenbahnGeschichte 52 (2012), pp. 12–21.
- Andreas Geißler, Konrad Koschinski: 130 years of the East Railway Berlin - Königsberg - Baltic States. Published by Deutsche Bahnkunden-Verband e. V. GVE, Berlin 1997, ISBN 3-89218-048-2 .
- Albert von Mühlenfels: East Prussia, Danzig and the Polish Corridor as a traffic problem , writings of the Institute for East German Economics at the University of Königsberg, vol. 1. 1930.
- Reichskursbuch 1914, Table 21, pp. 50/51
- Reichskursbuch 1905, Table 21, pp. 38/39
- Wilfried Biedenkopf: Across Old Europe: The international train and coach runs according to the status of summer 1939. Publishing house and office for special traffic literature Röhr, Krefeld 1981, ISBN 3-88490-110-9 , p. 20.
- Siegfried Bufe, Bernhard Schülein: Königsberg Express , Bufe-Fachbuch-Verlag, Egglham 2002, p. 42
- Official course book for the Reich, summer 1934, table 117, p. 146
- Siegfried Bufe, Bernhard Schülein: Königsberg Express , Bufe-Fachbuch-Verlag, Egglham 2002, p. 63
- Siegfried Bufe, Bernhard Schülein: Königsberg Express , Bufe-Fachbuch-Verlag, Egglham 2002, p. 68
- Siegfried Bufe: Shifted borders. Memories of the D 1 Berlin - East Prussia - Baltic States. In: EisenbahnGeschichte 52 (2012), pp. 12–21
- Herman Gijsbert Hesselink, Norbert Tempel: Railways in the Baltic States. Lok-Report publishing house, Münster 1996, p. 65