Brussels South (Midi/Zuid) Railway Station

We're in the midst of prepping our Brussels city content for the site and I thought I'd post a quick tip for train-riding tourists to this town:

Free train ride
I stayed in a hotel on the south side of Brussels and hopped aboard a train that took me to Brussels Central (Bruxelles Centraal) station--about a 5-minute ride. Inside the large Brussels South (Midi/Zuid) terminal, television screens showing route details hang from the ceiling at the bottom of escalators that zip riders up to separate platforms. The screens are easy to read and follow, but if you want to ensure boarding the correct train there are helpful information booths staffed by workers in the station's center as well.

The first time I rode from Zuid/Midi to Centraal, I paid the fare (can't remember exactly how much--maybe 2 Euros?). But after the short trip I realized nobody checked my ticket?? So, on my return trip from Centraal station back to the Midi/Zuid station I boarded without a ticket...and again nobody checked. The following day I rode back and forth again without purchasing a ticket.

While I'm not certain if riders are supposed to buy a ticket for that short commute, it certainly seems that the local authorities don't care.