The 11th edition of the Empuries marathon, half marathon and 10K races will be held on Sunday April 28th in Empuries near L'Escala (Costa Brava).
The race goes through the historic Roman ruins of Empuries and the town of L'Escala. On a nice day, the small peninsula of Cadaques can be seen easily. The price of the marathon is €29 euros, significantly lower than the Barcelona marathon.
All the details are here: http://www.maratoempuries.org/ (Catalan, Spanish, English and French)