Transportation - Get In
Air France and Gabon Airlines fly from Paris to Libreville, and Royal Air Maroc flies from Casablanca to Gabon. Air Service also flies to Douala (Cameroon), and Ethiopian Airlines flies from Addis Ababa. There are also on occasion flights to Brazzaville, Congo.
Interair flies from Johannesburg (South Africa) to Libreville on Monday with a stopover in Brazzaville/Congo - returning via the same route every Wednesday. "SAA" flies direct from Johannesburg (South Africa) to Libreville on Wednesdays and Fridays.
Lufthansa flies five times weekly from Frankfurt.
There are several border crossings, though the roads are not good and a 4x4 is recommended.
Transportation - Get Around
The easiest way to get around outside of cities is by bus (typically 6- or 9-seater cars, but sometimes minibuses). There are many and they are very cheap (e.g. 7000 XAF to go from Libreville to Lamberene). Within cities, taxis are plentiful and are very cheap. No fare should be more than 5000 for one person. Fares depend on distance (and whether the driver will be able to find more fares at your destination). A 2 or 3 minute drive will cost 100 XAF, and 2000 XAF is plenty to go from Owendo train station to the centre of Libreville. Taxi prices typically double after 21hr.
Air Service has scheduled flights to Oyem, Makouko and Franceville/Mvengue. Air Nationale flies to Franceville/Mvengue. There are flights to Franceville/Mvengue every day of the week except Tuesdays and Thursdays. Africa's Connection has daily scheduled flights between Libreville and Port Gentil, weekly flights from Port-Gentil/Libreville to São Tomé & Príncipe and to Loango National Park.
There are some paved roads in Gabon, if you are staying in one of the major cities a car should suffice. If you plan on venturing onto some of the unpaved roads outside the major cities a 4x4 is required. There are less than 800km of tarred roads in Gabon - some of them in a bad condition. During the rainy season it is difficult to travel outside the major city areas even in a 4x4 vehicle.
The Trans-Gabon railroad goes from Owendo to Franceville. The trip takes 12-18 hours, and is often delayed. Train times change according to the season. The current timetable (Basse 2014 as of March 2015) has trains both ways on Tuesday, Thursday, Friday, and Sunday. Two different trains are in use - the Omnibus and the Express. Both take a similar time, but the Express stops at less small stations. Air-conditioning is present in VIP, 1st and 2nd on the Express, and only VIP and 1st on the omnibus.
A few wealthy Gabonese entrepreneurs have invested in new buses for bus lines to service the larger interior cities. Mostly these buses serve the cities with paved roads leading to and from them. Since Air Gabon closed down, these bus lines have greatly increased their routes.
Boat travel is available all along the coast of Gabon and dozens of miles up the Ogooue river to Lambarene. Boats leave daily to/from Libreville and Port Gentil. River trips from the mouth of the big river at Port Gentil to Lambarene (Albert Schweitzer Hospital) are available every few days. Hotel Olako arranges weekly boat transfers between Port Gentil and Omboué (close to Loango National Park), transfers take between 3 and 4,5 hours (depending on the type of boat and engine).