The project of the Eurocity Baiona - Donostia supposed a great challenge to future to overcome the interior borders of the European Union and to develop joint and balancely a region established on both sides of the Bidasoa river. However, the results after one decade do not seem to be excessively optimistic. The political - administrative handicaps, the lack of wills and wide bottoms has given to the fret or these have not developed suitably all that itwas planned in a beginning. Though, the general result has not been excessively satisfactory yes have existed interesting points of development and, with a view to the future, this project still counts on an evident interest.