Probably the most comfortable way to travel between Keflavik airport and Reykjavik centre. It is isn't the cheapest, but still worth it compared to inconvenience of public bus travel with Strætó.

• Company is called Reykjavík Excursions (but there's also another one called Airport Direct)

• They also offer drop off and pick up at many of the hotels around the city for an extra charge.

• You can either buy the ticket online or at the airport terminal. I've also paid at the bus once, but they prefer you to have the ticket already purchased beforehand.