Molins de Rei or Molins de Rey in Spanish is a municipality located 18 km from Barcelona's city centre, in the comarca of Baix Llobregat in Cata…Molins de Rei or Molins de Rey in Spanish is a municipality located 18 km from Barcelona's city centre, in the comarca of Baix Llobregat in Catalonia, Spain. It is situated on the left bank of the Llobregat river, on the A-7 autopista from Valencia to La Jonquera and the main N-II road.