Where is the first race in the grand prix season?

Often Grand Prix refers to Formula One racing, and the first Formula One Season was in 1950. Here is the list of races in order of when they were held:

• British Grand Prix: May 13, 1950 at Silverstone Circuit
• Monaco Grand Prix: May 21, 1950 at Circuit de Monaco
• Indianapolis 500: May 30, 1950 at Indianapolis Motor Speedway
• Swiss Grand Prix: June 4, 1950 at Circuit Bremgarten
• Belgian Grand Prix: June 18, 1950 at Circuit de Spa-Francorchamps
• French Grand Prix: July 2, 1950 at Reims-Gueux
• Italian Grand Prix: September 3, 1950 at Autodromo Nazionale Monza

Grand Prix means "grand prize" in French, and there are a lot of contests that have events with that name, so if you were expecting a different answer, it depends on which "Grand Prix" you mean and you might want to ask a more specific question.