The SWL spanish callsing estructure has been different depending of his time of use. We have the following estructurs:
1 ) EA + order (all of them before the Spanish Civil War 1936), ie. EA-111
2) E + order (alos used before the Spanish Civil War 1936, ie. E-111
3) E + district number + order, ie. E-1-111
4) España + district number + order, ie. España 1-111
5) EA + district number + order+ U (optional), ie. EA1-1111-U
6) EA + district number + province code + order, ie. EA1-01-11111
Here you have a new galery with some spanish SWL qsl samples: