Legend and legacy are only worth so much. And while Spa-Francorchamps remains one of the great tracks on the grand prix calendar, anyone arguing that Suzuka has not long since superseded it as the greatest driver challenge in Formula 1 is living in the past.
Grand prix circuits are defined by two things. Based on one of them, the ribbon of asphalt itself, Spa probably has the edge. But the real character of a track is defined by what lies beyond it. And, once you take that into account, Suzuka wins hands down.
At Spa, for very sound safety reasons, much of the circuit is lined by asphalt runoff. Thankfully, given some of the horrendous accidents at the Belgian track in the past, mistakes are not punished as harshly as they once were. But it also means that drivers can get away scot-free with most errors.