Complex sentence: Manuel Fernando Soares Pinho (2005) It is likely that a medieval castle existed in Argifonso, since some structures and a castro were discovered in the vicinity, but Moorish influences in the Iberian peninsula only occurred at the end of 711.
Split into simpler sentences: Manuel Fernando Soares Pinho (2005) It is likely that a medieval castle existed in Argifonso, because some structures and a Castro culture were discovered in the vicinity. However, Moorish influences in the Iberian peninsula occurred only at the end of 711.