Montcada i Reixac Main Festival Activity · Montcada i Reixac, Vallès Occidental, Barcelona Image of Montcada i Reixac, not of the place itself. The Festa Major of Montcada i Reixac is celebrated in spring (at the beginning of June or the end of May depending on the year), and the municipality also keeps the feast of the Mare de Déu de la Mercè on 24 September. Photo: pere prlpz (CC BY-SA 3.0) What to see and do in Montcada i Reixac