We are flying from Gatwick (LGW) to Oslo Gardermoen (OSL) and then to Tromso (TOS) with Norwegian Air.
Norwegian are due to start direct flights from Gatwick to Tromso later this year. Just too late for us.
The flights are both about 2 hours long & we have a 3 hour wait at Oslo each way. Long enough to be annoying if everything runs to schedule but hopefully sufficient to cope with any hiccups with the first flight on each journey. It does mean that with check-ins we’ll be travelling for about 11 hours which is quite long enough for a journey within northern Europe.