That used to be called the San Marino GP at the Autodromo Enzo et Dino Ferrari track, I was there ages ago and enjoyed standing with the tifosi at Tosa. I came in my own car from the holiday resort Viarregio on the west coast and stayed at the Garden Hotel there which is said to be haunted if you're into the supernatural
Temps are around 21C in May and more for a relaxing stay here than say Milan where you'll be racing around shops, places of interest etc.