The Interrail rules state :
3.2 Travel in Country of Residence with an Interrail Global Pass
An Interrail Global Pass may only be used for two specific trips in
the country of residence of the traveller (provided this country is an
Interrail participating country). These two trips are referred to as
the outbound and inbound journey.
- The outbound journey can be used to travel from any location in the country of residence to the border or an airport or port.
- The inbound journey can be used to travel from the border or an airport or port back to their (final) destination in the country of
residence.
During these trips, the traveller may travel with more than one train,
provided the trips are within the same day. Please note that the
special rule for travel with an overnight train also applies. In order
to make use of these trips, the traveller must indicate the relevant
date and journey on the Interrail Pass Cover and on the Travel
Calendar, in case of a Flexi Pass.
Is this allowed under Interrail rules?
I don't know how this wouldn't be, but that Zürich-Dunkirk would very much be allowed under the Interrail rules (for way cheaper too, a ticket for tomorrow from Zürich to Mulhouse can be found for €50)
Do I need to purchase two separate seat reservations (Zurich-Mulhouse, Mulhouse-Dunkirk) or would just one work as well? (Zurich-Dunkirk)
If you buy a separate ticket from Zurich to Mulhouse, you will only need the relevant seat reservation for the Interrail segment
