There are a number of modes of transportation in Seychelles. Seychelles possesses transport systems which include: 453km of roads(of which 400km are paved), seaports and airports. The country lacks railways. The main seaport is Victoria, and Seychelles has no merchant marine. There are fourteen airports in Seychelles, the major ones including Seychelles International Airport and Praslin Island Airport. Of the fourteen airports, six have runways that are paved. The blue, government-run SPTC buses are the primary form of public transport and the cheap way to travel. They run main routes on both Mahé and Praslin islands daily between 5:20 a.m. and 9:30 p.m., every 15 minutes or so. Buses are air-conditioned and comfy enough, although it is best to avoid long distances on Mahé as the island is hilly and drivers test the speed limits. Schedules are also a bit unreliable.