Spanish low-cost airline Vueling is the largest airline in Spain by fleet size and number of destinations. Also member of IAG family (British Airways / Iberia). Vueling has just released new promotional sale in 2018. This time offering greatly discounted domestic flights across Spain available already for 9.99 each way! Vueling with its HQ at Barcelona El Prat airport. (Secondary at Rome Fiumicino) is connecting many Spanish cities as well as other main markets in Europe.
Vueling promo sale is runnig only till 5th of September. Look for discount when traveling between 16th of October 2018 and 30th of March 2019. Simply follow below special link where you can find all discounted routes available. Once you proceed you will see low-cost calendar by each month so you can easily
Booking sample of current Vueling promotion: Fly across Spain from just €9.99 each way! In this case you would depart from Barcelona to Madrid on 16th of November. Return flight would be then on 19th of November. You would pay total €19.98 for a return ticket.