Tromsø (airport code TOS) is best reached by plane, most conveniently via Oslo (but read on); flight time is just below two hours. Two airlines service Tromsø, SAS and Norwegian. While Norwegian is a low-cost airline, connections from Oslo are generally better with SAS.
SAS is a member of Star Alliance, thus has code-sharing agreements with, among others, United, US Airways, Lufthansa and Air Canada. If you are coming from North America, be aware that there is only one intercontinental flight from/to Oslo (Newark, with Continental); the SAS intercontinental hub is Copenhagen, good connections to Oslo are also available via London Heathrow, Amsterdam, Paris and Frankfurt. You can book tickets to Tromsø via the SAS website from most major North American airports. In addition, SAS or one of its partners flies to all major European airports.
While Norwegian is generally cheaper than SAS, connecting flights to destinations outside Norway are scarce. You would have to buy two tickets (Tromsø-Oslo and Oslo-wherever) and ensure that there is ample connection time because if your first plane is delayed, you will not be re-booked. Norwegian does have connections to a relatively large number of European airports, however. Norwegian is the only airline that has a direct flight to Tromsø from outside Scandinavia. You can fly directly from London Stansted, although only Tuesdays and Saturdays. Bear in mind, however, that Stansted is quite far away from London, and transfer from either Heathrow or Gatwick takes several hours.
Note that very few low-cost airlines fly to Oslo. Besides Norwegian, the only other option is Sterling. Ryanair offers flights to 'Oslo' but that means Sandefjord, from where it should take you about 3 hours to Oslo Gardermoen airport (there are no flights to Tromsø from Sandefjord).
Tromsø airport is a few miles from the city centre. To get to the centre, you can take a taxi (150 NOK; the taxi rank is just outside the terminal building) or a shuttle bus ('flybussen') which stops at the major city centre hotels (55 NOK). Alternatively, take bus routes 40 or 42 to the city centre (25 NOK; the bus stop is c. 100 metres from the terminal building). Please note that most busses do not ride on Sunday before noon. Bus information can be found at http://www.cominor.no.
For further details, see also CASTL information for visitors at http://uit.no/castl/3694/.
All hotels are located around the city centre.
Address: Skolegata 24
Phone: +47 77 62 10 00
Stay economically, but nicely, in relaxed and clean surroundings in central Tromsø.
ABC Hotel Nord
Address: Parkgata 4
Phone: +47 77 66 83 00
The hotel comprises 22 rooms, with a total of 39 beds. We have six rooms with private bathroom. All rooms have a sink with hot and cold water. The hotel is situated in a side street in quiet surroundings around 400m from the city centre. Welcome!
Address: Storgata 105
Phone: +47 776 295 00
City Living Hotel, Tromsø
Address: Grønnegata 48, 9008 Tromsø
Phone: +47 77 78 10 50
This is a new hotel with 46 high standard rooms and apartments, ranging in size from 14.5 sqm to 52 sqm. All rooms have en suite bathrooms, kitchen facilities, fridge, TV and free internet access. The larger rooms also have dishwashers. There is a guest laundry with a washing machine and clothes dryer. Check-in outside opening hours is by self-operated check-in machine.
Clarion Hotel Bryggen
Address: Sjøgata 19-21
Phone: + 47 77 78 11 00
Tromsø's newest and most modern hotel. Ideally located on the quayside and in the city centre. Relaxation area featuring sauna and outdoor spa pool. Astro restaurant, bar and conference facilities.
Address: Fredrik Langesgate 2
Phone: +47 77 66 64 00
Beautifully located right on the quay in the centre of Tromsø, with views over the Tromsø Sound, Arctic Cathedral and Tromsø Bridge.
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More accommodation can be found at http://www.destinasjontromso.no/.