InterRegio

The InterRegio system was also introduced to the Danish railways in the early 1990s and became an alternative to the InterCity services, with no seat reservation required.

However, unlike other countries, InterRegio trains in Denmark only operates on Fridays and Sundays, to support the heavy flow of passengers that travel on those days.

[citation needed] The InterRégió trains were introduced in Hungary on 12 December 2009 (15 years ago) (2009-12-12).

InterRégió trains use air-conditioned MÁV 6341 DMU-s which were built by the Russian Metrovagonmash.

In the beginning these trains operated mostly on Fridays and Sundays along the routes: Wrocław-Kraków, Kraków-Przemyśl, Poznań-Olsztyn, Poznań-Warsaw and Bydgoszcz-Warsaw.

Since 1 September 2015 IR trains are only on routes Łódź – Warszawa and Ełk – Grodno (Belarus), due to company's economics and restructuring.

The ICN runs as an InterCity (IC) train but sometimes with halt frequencies in the same manner as an IR (Geneva/Lausanne-St. Gallen/Basel route).

As of the December 2024 timetable change,[update] the following InterRegio services exist, operated by SBB CFF FFS, BLS, RhB and SOB: In Belgium, InterRegio (IR) trains were slower than the fast IC trains, and usually called at more stations along a route.

However, Interregio-Express lines belong technically to the short distance train category, and tend to be shorter.

Since 2010, the former interregional trains received the new category treno regionale veloce (RV/RGV), lit.