Not many of us will have been lucky enough to visit all the F1 venues, but I've always liked the look of Spa on the TV, although I've never been there. Bahrain doesn't look so promising, neither do the other circuits where overtaking is nearly impossible (Monaco excepted).
My favourites are Spa, Montreal and Albert Park. They're all great circuits but I like others such as Monza or Istanbul Park
I liked estoril, can remember Mansells pit stop and his ultimate disqualification was pleased for ricardo though. Also sentimental about Canada, Alesi winning his only GP of his entire F1 career, very emotional.
I used to really enjoy the Old layout of the Hockenhiem track, It always pulled out good races and was all about speed with a mix of cornering in the stadium section. Nowadays my fav tracks are Monza, Melbourne and of course Silverstone