The boss of the Nurburgring is unsure whether this weekend's race will be a one-off for the former Formula 1 venue.

Alongside Mugello, Portimao, Imola and Istanbul, the German circuit is among those who are filling in the gaps in F1's hastily-compiled 'corona calendar'.

One criteria for the inclusion of some of those circuits is that local authorities have green-lighted the return of spectators, following the early 'ghost races'.

However, Istanbul's plans for up to 100,000 spectators has fallen through, with the government now announcing that fans will no longer be allowed at the 15 November event.

"As part of the efforts to combat the coronavirus epidemic, and in accordance with the recommendation of the Istanbul Provincial Pandemic Committee, the Turkish GP will take place without spectators," read a statement.

20,000 fans will be at the Nurburgring this weekend, though - even though the weather in the Eifel region in October is typically inclement.

"Even snow is not impossible," commented German former F1 driver Ralf Schumacher. "The weather is promising to be very entertaining for the audience."

As for the circuit's chances of returning to the calendar in 2021, Nurburgring boss Mirco Markfort is not so sure.

"Of course we will try to keep Formula 1 in the future, but that also depends on the general conditions in the world - whether that is corona or the economic consequences of corona," he told Sport1.

"Doors can open for us, but that's all speculation."