The line was, from the start, planned and opened as a double track route, with trains travelling on the right. It had been intended to switch to running the trains on the left side of the double track once the line had been extended and connected with the main Paris-Strasburg line, but this was not done. After the
transfer of
Alsace into
Germany in 1870, the region's railways were integrated into the German rail network, where travelling on the right-hand track of any double track was already standard procedure, so there was no longer any pressure for railways to switch to the French convention of running trains on the lefthand track. In 1919 and again in 1945 the region reverted to French control, but on the Strasburg-Basel line, as in the rest of Alsace where twin tracks are involved, trains continue to travel on the right. ==References==