How convenient is this to the airport (Gardermoen) in terms of transportation options?
The Shuttle train called Flytoget runs from the airport every 10 minutes and it takes 22 minutes to National Theater station. From there you can take tram nr. 13 in direction Lilleaker/Bekkestua 3 stops and get off at Skillebekk. It is 1 minute walk from Skillebekk tram station to the hotel. It is also a 5 minutes drive if you take a taxi to the hotel from the National Thetaer or 15 minutes walk. The price for the shuttle train per person is about 170 NOK, whereas the fare for an airport taxi is around 759 NOK at a daytime. So if you are more 4 people it is better to take a taxi. NB! Make sure you order specifically an airport taxi to get a fixed price, otherwise they may charge you by a taximeter and it may be much more expensive.
We took the express train. There is a cheaper way, the commuter train. They both leave from the airport and both go to the Oslo Central Station. We walked from there all the way to the Gabelshus first time ( 4km ), after that we always took tram # 13. It was perfect and inexpensive. The 13 stops 1 minute walk from the hotel. Taxi in general is very expensive everywhere in Scandinavia, but public transport is extremely well developed and affordable.
The previous answer is accurate except that if there are 2 or 3 people travelling, the cost of a taxi from the hotel to the airport may not be much more than a taxi to the train station and the train to the airport. The tram to the train station is cheap but it doesn't run 24 hours a day so, if you plan on using it, make sure it's running when you need it. I cannot remember exactly what the taxi fare was but we asked the very accommodating people at the hotel front desk to reserve one for us (they were able to tell us what the fixed rate would be) and, as I recall, it was less than $100 and much easier for an early morning flight with several suitcases. Hope this is helpful. Coming into the hotel from the airport, the train and a taxi (or tram, if you know which one to take) from the station is not a problem although even though the national theater station is pretty close the the hotel, the taxi fare from there in rush hour may be nearly as much as the train ticket from the airport.
There is an express train link running every 10 minutes from the airport into Oslo station which is in the centre of the city. As the airport is a substantial distance out of town, this is the best option (a cab would be VERY expensive). Once at the station, you may wish to get a cab (five minutes) to the hotel. The number 13 tram runs from the station to the bottom of the road the hotel is in.
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