Festivities of Sant Mateu Activity · Sant Mateu, El Baix Maestrat, Castellón Image of Sant Mateu, not of the place itself. Sant Mateu's patronal festival runs from 18 to 29 August in honour of Santa Tecla and Sant Climent, with the traditional ball pla on the 20th; the town also has as patron saints the Virgen de los Ángeles and San Mateo Apóstol, celebrated on 21 September. Photo: DagafeSQV (CC BY-SA 3.0) What to see and do in Sant Mateu