In June, Campbell left Portugal for Spain, going to Salamanca and then to Toledo, where he retrieved the personal papers of Saint John of the Cross from a hiding place in his former flat. Campbell then attempted to enlist in one of the Carlist militias, but was informed by Alfonso Merry del Val, the head of the Nationalist Press Service, that he could better serve as a war correspondent alongside Franco's armies. Travelling on a journalist's pass issued by Merry del Val, Campbell left Toledo on 30 June 1937 and was driven to Talavera, where he suffered a serious fall, twisting his left hip. The following day, the special car traveled southwards from the front, ending its lightning tour in Seville. This visit appears to have been Campbell's only front line experience of the war. However, that would not keep him from later suggesting that he had seen far more action than he had. He did not fight for the Nationalists during the Spanish conflict, despite later claims.