Late entries from Muddy - Maybe it's the era that I remember with rose-tinted glasses, maybe it's that the cars were capable of overtaking and were varied, but I like and miss these
Rio de Janeiro
Mexico
Of the current circuits, Montreal and Spa of course (they've even managed to make the bus-stop a better corner)
Special Mention - I don't remember F1 at Watkins Glen, but it looks a bit of a doozy in NASCAR
These can be erased from my memory
Aida
Jerez
Valencia
Special Mention - Caesars Palace, despite it being the scene of Keke winning his WC and Carlos Reutemann miserably losing his the year before