Route notes
Why this routing works
This multi-stop itinerary is built as an open-jaw route: Saint Louis to Reykjavik, then a separate overland segment to Jersey, followed by a flight to Paris and the return to Saint Louis. That structure works well when one section is intentionally left off the ticket, while keeping the long-haul and intra-Europe flying on the same plan.
With 7 nights in Reykjavik and a total trip length of 3 weeks, the timing leaves room to spread the remaining days across Jersey and Paris without forcing immediate connections. The sequencing also keeps the overland transfer in the middle of the trip rather than at the start or end, which can simplify the transatlantic planning.
Ticketing-wise, this is a premium-economy MSI rather than a simple round-trip, which matters because the route does not return directly from the first stop. September travel within the July-to-September season can be a practical fit for this kind of Europe-focused multi-stop, especially when combining one fixed stop duration with an open-jaw section.