2. Batu Tiga Speedway Shah Alam (Malaysia) - In 1995 Malaysian Grand Prix was poised to be on F1 calendar at Batu Tiga Speedway thanks to Petronas's presence but F1 rejected that plan due to Batu Tiga Speedway deemed too short and unacceptable for F1. BTSC now defunct and turned into houses complex since 2003.
3. Circuit Ricardo Tormo Cheste Valencia (Spain) - Used as F1 pre-season testing track in the past but never used as regular Grand Prix race due to Valencia Cheste circuit too short.
4. Sentul International Circuit (Indonesia) - In early 1990s Indonesian president Soeharto was dreamed of Indonesian Grand Prix F1 race at Sentul International Circuit at least in 1994 or 1995 due to Sentul Circuit is owned by Tinton Soeprapto (Soeharto's closest alliance) but Sentul chooses MotoGP GP 500cc instead rather than F1 due to Sentul Circuit deemed too short as shorter circuit not acceptable for F1 calendar and also lack of state government funding support. At least Sentul Circuit ever hosted A1 Grand Prix race twice in 2006 (February and December).
5. Buriram Circuit (Thailand) - Suitable for F1 due to Alexander Albon's presence factor but one day Thai Grand Prix will be included on F1 calendar.
Any additions?
