territories of Germany, i.e. East Prussia, Farther Pomerania, and Silesia; these territories became parts of Poland and the Soviet Union with the implementation of the Oder–Neisse line after World War II. Parts of the planned autobahn from Berlin to Königsberg (the Berlinka) were completed as far as Stettin (Szczecin) on 27 September 1936. After the war, they were incorporated as the A6 autostrada of the Polish motorway network. A single-carriageway section of the Berlinka east of the former "Polish Corridor" and the Free City of Danzig opened in 1938; today it forms the Polish S22 expressway from Elbląg (Elbing) to the border with the Russian Kaliningrad Oblast, where it is continued by the R516 regional road. Also on 27 September 1936, a section from Breslau (Wrocław) to Liegnitz (Legnica) in Silesia was inaugurated, which today is part of the Polish A4 autostrada, followed by the (single vehicle) Reichsautobahn 9 from Bunzlau (Bolesławiec) to Sagan (Żagań) the next year, today part of the Polish A18 autostrada. After the German occupation of Czechoslovakia, plans for a motorway connecting Breslau with Vienna via Brno (Brünn) in the "Protectorate of Bohemia and Moravia" were carried out from 1939 until construction works discontinued in 1942. A section of the former Strecke 88 near Brno is today part of the D52 motorway of the Czech Republic. Also, there is the isolated and abandoned twin-carriageway Borovsko Bridge southeast of Prague, on which construction started in July 1939 and halted after the assassination of Reinhard Heydrich by former Czechoslovak army soldiers at the end of May 1942. Current density , Germany's autobahn network has a total length of about . From 2009 Germany has embarked on a massive widening and rehabilitation project, expanding the lane count of many of its major arterial routes, such as the A 5 in the southwest and A 8 going east–west. Most sections of Germany's autobahns have two or three, sometimes four lanes in each direction in addition to an emergency lane (hard shoulder). A few sections have only two lanes in each direction without emergency lanes, and short slip-roads and ramps. The motorway density in Germany is 36 kilometers per thousand square kilometer in 2016, close to that of the smaller countries nearby (Netherlands, Belgium, Luxembourg, Switzerland, Slovenia). Facilities Emergency telephones About 17,000 emergency telephones are distributed at regular intervals all along the autobahn network, with triangular stickers on the armco barriers