This little 18xx add-on expands the 1835 board to the north-east. It also introduces another Minor Company, the Ober-Schlesische Bahn (4a) which replaces the Koln-Mindener Bahn (4) and works like any other pre-Prussian railroad. The expansion also included 1 overlay tile for Berlin, 2 more 2-trains, a company charter and a token for the new railroad.