Asturias is relatively well served by public transport, especially along the coast, with rail links in all directions via two rail companies, FEVE and RENFE, and links to all over Spain by bus too.

Asturias Airport

The Aeropuerto de Asturias is Asturias' only airport, and has flights to domestic and international destinations.  With regards to getting to and from the airport with public transport, there are two options.  Taxis at the ranks at the airport will take you to any destination you wish at a price, alternatively there also buses from the airport.  Run by ALSA, these buses leave from outside the terminal and have various destinations.  There are two direct shuttle type buses, one to Oviedo, and one to Gijon.  There are also further buses with more stops to destinations including Avilés, Salinas and a few other places in Asturias.  For most other destinations in Asturias however, it is necessary to change at the bus stations in either Gijon or Oviedo.  There are buses from the airport to other Spanish destinations too, have a look on the airport bus section of the ALSA website for timetables, prices and ticket purchase.

Bus Travel

Asturias is served by various bus companies, providing bus transport to a large area of the province.  Oviedo bus station  is the main hub for bus transport in Asturias, being so central, and from here there are many national buses, mainly provided by ALSA, and local buses too.  Another website which is useful for the whole of Asturias is that of the Consorcio de Transportes de Asturias, where bus times can be found, albeit in a slightly wierd Google format.  Alongside general bus times, this site also gives information on getting to Covadonga by bus, getting to Poncebos by bus (for the Cares Gorge Walk and Bulnes funicular) and night buses around the central area.

Train Travel

Asturias is served by two train companies, the national RENFE line going south towards Madrid, and the narrow gauge FEVE lines.  It is important to note that on rail booking sites such as RailEurope, the FEVE lines are not recognised and often simply don't appear as an option as they are not a national rail network and tickets cannot be bought in advance.  

RENFE

RENFE trains have a mainline service connecting Gijon, Oviedo, Mieres-Puente and Pola de Lena with Leon, Palencia, Valladolid and Madrid.  There are around 3 daily from Gijon and 4 daily from Oviedo. RENFE also run local Cercanias trains around the central area of Asturias with 3 lines running Oviedo-San Juan de Nieva (incl. Avilés), Oviedo-El Entrego (east), and Gijon-Oviedo-Puente de los Fierros (south), for a map of these see here.

FEVE

FEVE trains have various routes in Asturias, both locally and connecting with Galicia and Cantabria next door.  Internally, there are lines from Gijon-Laviana, Gijon-Cudillero, Oviedo-San Esteban de Pravia and Oviedo-Infiesto. There are then further routes from Oviedo, one connecting Oviedo with Ferrol in Galicia, essentially going along the west coast of Asturias, including stops at Cudillero, Luarca, Navia and Castropol and crossing the border at Ribadeo, and another going east to Santander in Cantabria (where there is a FEVE connection on to Bilbao), again taking a coastal route to include Ribadesella and Llanes, and crossing the border in Unquera. As previously mentioned, tickets for FEVE trains are not bookable in advance, however you are very unlikely to have trouble getting tickets as they are mainly used as commuter trains over short distances and are not long distance. This also means that they do take longer (although more picturesque), if you are in a hurry take the bus. Maps of the FEVE routes can be found here.

Tourist Trains

Additionally the FEVE company also run tourist trains across the north of Spain.   The Transcantabrico, which runs from Ferrol in Galicia to Bilbao (with coach links to Santiago de Compostela and San Sebastian) is probably the most popular, passing through Oviedo and Santander.  There are two classes, the Transcantabrico Clasico and the Transcantabrico Gran Lujo. In Asturias there is another train, the Estrella del Cantábrico, which runs two routes, the Itinerario de la Santina from Gijon to include Covadonga and the Itinerario de Biosfera also from Gijon to include the Parque Natural de Redes.  These last two trains run on specific days from July-September, and must be reserved in advance (possible online).