Belfort is a city in France.
Go to Avenue de la République with a sign Besançon. The next gas station is just before Besançon so you have to go there at least. It took me one hour to stop a car while it was snowing.
In my experience, the ideal place is at the Mendès France bus station, near a petrol station. There's a lot of traffic going to the highway in both directions (Paris-Lyon-Besançon, and Strasbourg-Colmar-Mulhouse), and the bus station allows the car to stop easily. It took us only 5-10 min to get a lift to Besançon.