Poor timetable
These are the times of the main RegionalExpress (RE) trains arriving in Aachen Hbf in the middle of the morning (the same times repeat every hour all day):
D. Düsseldorf Hbf 10:21
A. Aachen Hbf 11:35
RE4 via Neuss Hbf, Mönchengladbach Hbf, Herzogenrath
D. Köln Hbf 10:15
A. Aachen Hbf 11:07
RE1
D. Köln Hbf 10:47
A. Aachen Hbf 11:41
RE9
And this is the time of the hourly RE29 train to Welkenraedt in Belgium, and onwards to Verviers and Liège
D. Aachen Hbf 11:37
A. Welkenraedt 11:52
Yes, the train departs just 2 minutes after the RE4 arrives (too tight to connect), and 4 minutes before the RE9 arrives. The connection with the RE1 – 30 minutes to change – is the opposite, as it is longer than ideal. It is hard to imagine how it would have been possible to timetable the RE29 worse than this.
But what about Belgian side?
From Welkenraedt there are normally 2 InterCity trains an hour to Bruxelles and beyond:
D. Welkenraedt 11:25
A. Bruxelles Midi 13:00
IC 534
D. Welkenraedt 11:49
A. Bruxelles Midi 13:30
IC 434
The RE29 from Aachen connects with neither of those either – you have to wait for the 12:25 IC 535 – so a 33 minute wait in Welkenraedt. Yes, this hourly cross border service does not connect properly with anything on either side of the border.
In the other direction it is no better.
D. Welkenraedt 10:06
A. Aachen 10:22
D. RE1 to Köln – 10:51 (29 minute wait)
D. RE9 to Köln – 10:18 (missed by 4 minutes)
D. RE4 to Düsseldorf – 10:22 (same minute as RE29 arrives)
And from Bruxelles Midi
IC from Bruxelles Midi arrives Welkenraedt 10:09, IC 407 (misses Aachen train by 3 minutes), so you have to take the earlier IC 506 arrives Welkenraedt 09:33 (36 minutes waiting time).
European Commission Analysis
Details to be added
Photos from this location