I would like a clarification as to which trains are covered. Is it all trains or just slow trains?
What do you mean by a "Twin Rail Pass"?
Is this a (1) Länder ticket, a (2) Schöneswochenende Ticket or a (3) "German Rail Pass"?
If it is one of these 3, the answers are (in order):
(1) Valid on Regional trains only, NO IC or ICE. On weekdays only valid after 09:00. Also valid on U-Bahn and buses.
(2) Valid on Regional trains only, NO IC or ICE.
(3) Valid on all trains, but some trains run by independent companies may not be covered. Only available if you live outside Europe, leaflet here: https://www.bahn.com/en/view/mdb/bahnintern/international/redaktion_bahn.com/pdf-datein/pdf_2018/mdb_268059_german_rail_pass_2018.pdf
Can you clarify what you mean?
Or 4) Eurailpass Saver for two people ?
a german rail twin pass
A German Rail Twin Pass is valid on all German Rail trains, including the fast trains like the ICEs.
(1) Valid on Regional trains only, NO IC or ICE. On weekdays only valid after 09:00.
Also valid on U-Bahn and buses.
To clarify, the S-Bahn is a regional train of the Bahn and therefore covered by a GRP or Länder ticket. Also covered by a Länder-Ticket (incl. SWT and QdLT) are U-Bahn, trams, and buses in the various Verkehrverbünde (metro districts) as well as many regional buses, like RVO in Bavaria.
great info...thanks to all