 Complete the following phrase:  After World War II, Barcelona started playing host to the Formula One auto and Grand Prix motorcycle racing. The first circuit used in Barcelona was at Pedralbes in 1951, where the inaugural race was won by Argentinas Juan Manuel Fangio. One more race was held at Pedralbes in 1954, won by Great Britains Mike Hawthorn. Formula One would not return officially to Spain until 1968 though Barcelonas Montjuïc circuit would share duties hosting with Circuito del Jarama to 1975 with Monjuïc hosting in odd-numbered years. The 1975 race was won by Jochen Mass of West Germany. In the former circuit, the Palau dels Esports de Barcelona was constructed in the north part of the circuit as part of the 1955 Mediterranean Games. Montjuïc Stadium was located south of the circuit as was the Piscines Bernat Picornell. Montjuïc hosted the Spanish motorcycle Grand Prix annually from 1951 to 1968 and then in even-numbered years until 1976. Formula One did not return to Barcelona until 1991 with the opening of the Circuit de Catalunya near Barcelona that would be won by Britains Nigel Mansell. The Brit also won the 