Amsterdam Time, also called Dutch Time was a time zone that existed in the Netherlands from 1909 to 1940. To make a national railway timetable possible, in 1909 a standard time was adapted. The timezone was GMT +0:40. So when it was 12 O'clock in Amsterdam, it was 11:20 in London and 12:20 in Berlin. When the Germans occupied the Netherlands the Berlin Time was adapted. The time zone wasn't rechanged after World War II.