Uploaded on 2018-11-30 by Hansjoerg Graf, 9450 Altstaetten, Switzerland

visible on my picture:3 Tracks (12, 13, 14), 3 pm above timetable for 30 minutes invisible A oldest (1847) and bigest station in Switzerland, 2600 passenger-trains per day (incoming and outgoing), 26 tracks 460 000 passengers per day invisible B all railways in Switzerland work on a «Takt-Fahrplan», all trains leave every hour at the same time in 15-, 30-, 60- or 120-minute intervals. There is little time for changing the trains, but that makes travelling very fast. Swiss trains are usually very accurate. That helps to shift the person transportation from the congested streets to the rail. But in the last few weeks, 20% of the trains on the main lines to Zurich were more than 3 minutes late, and many people so missed there connections. Selection of a problem and solution The railway officials don`t yet know the reasons for the delay. I can`t help them, but I hope, they know how to find out with Big Data (so that this invisible information can become knowledge and contribute to find back to trains with no delay). I arrived on one of this delayed trains. As a retired engineer. I had my coffee 5 minutes later.