One of the oldest circuits on the calendar (Nurburgring), a circuit which isn't even completed yet (Austin), Melbourne, Spa-Francochamps, Valencia. Bahrain shouldn't be seeing any F1 action either until the political mess is sorted out there, which given the presence of foreign troops/security on the street should take a while.
That's 6 out of 20 circuits threatened with extinction.
F1 in its current form is becoming an endangered species and not because of rule changes, lack of overtaking, scandals, or falling TV audiences.
F1 is facing extinction because it is not economically viable for the private sector to construct and manage modern F1 circuits; because Bernie charges €40 Million odd just to bring the race to your track. An operator needs to bring in 200,000 fans at €200 a pop just to pay that back! Not to mind the cost of updating circuits and facilities and paying back the massive debt you've incurred just by buying the land and constructing the complex.
Even if you accept that there should be some state input into the costs because of the TV exposure of the country and the boost to the local tourist economy, any such cash boost would not cover the cost of hosting the race and you'd actually be seeing the state subsidising the cost of tickets.
€40 million is far too much and a charge of €200 for a ticket is also well beyond the means of many F1 supporters when you include accommodation, flights, food, etc.
There is a serious drive within F1 teams to cut budgets to ensure the survival of the teams and this must also translate to the cost of putting on the races themselves. It's no good having 24 cars on the grid and 12 teams in a healthy economic state if you've got no circuits to race on.
I can afford to go to maybe one race every two/three years but they're all races located in Europe - I couldn't afford to travel to Malaysia, Korea, Suzuka (much as I'd like to), Abu Dhabi, Interlagos (much as I'd...) on any kind of regular basis and probably wouldn't bother trying to justify the expense (being married with a kid).
If F1 wants to survive it needs to reconnect on the ground. TV is all well and good but the wild beauty of the sport is only truly appreciated LIVE. Its what creates a visceral connection between the cars, the circuits, and the spectator and creates a life-long fan.
Bernie - Reduce your costs to the circuits. Circuits reduce your costs to the fan. Otherwise we'll be at the point where the only European Race will be Monte Carlo, there'll be no GP on the American Continent (except maybe Montreal, because that gets the US fans), there'll be no Antipodean GP, and all F1 activity will concentrate in Asia and the Middle East.
Au revoir Spa
Auf Wiedersehen Hockenheim
Adios Circuit de Catalunya (and I mean that one sincerely - unless it rains!)
It's been real.