Keflavik International Airport (KEF) handles virtually all international flights to Iceland and is one of the most important transit hubs in the North Atlantic. The airport is technically in the municipality of Reykjanesbær, immediately adjacent to Keflavik.
The Flybus (operated by Reykjavik Excursions) and Airport Direct run regular coach services to Reykjavik's BSÍ bus terminal, with journey times of about 45 minutes. Book in advance, though walk-up seats are usually available. Taxis to Reykjavik cost around 15,000–18,000 ISK (roughly €100) and make sense if you are a group. Local buses also connect the airport to Keflavik town centre.
The Blue Lagoon is 20 km from the airport via direct bus service — a convenient option on arrival or departure. Many visitors book a Blue Lagoon session timed to their flight.