My old Peugeot Partner (2003), can easily go 650 km with plenty of petrol left in the tank. I don't think 800 km would be out of the question.

Edit: according to the specs, it should have a range of 960 km (597 miles) under optimal conditions. It sounds more than I would expect, but then the car is almost 20 years old. Still, the low fuel consumption is one of the reasons I keep it -- it uses less fuel than modern hybrids do.