Beirut-Rafic Hariri International Airport (BEY) sits about 9 km south of the city centre and is the only international airport in Lebanon. Middle East Airlines, Lebanon's flag carrier, has the densest network out of the airport; major Gulf, European, and Turkish carriers all fly here too. Arrivals processing is usually quick, and a free visa-on-arrival is available for most Western passport holders.
From the airport, a taxi to central Beirut costs around 25-35 USD and takes 20-40 minutes depending on traffic. The official taxi desk in the arrivals hall fixes prices in advance and is far less hassle than negotiating with the kerb-side drivers. Uber and Careem also serve the airport.
There are no passenger rail or ferry services in Lebanon. Crossing the land border with Syria is not advisable in the current climate. From Jordan and most of the Gulf the only realistic way in is by air.