Lockdown restrictions began to be lifted in France on May 11 last. Except where exemptions applied, the rule governing permitted travel became as follows. Without special authorization, a person could travel to any place located:
within their department;
or within a 100 km radius of their home, measured "as the crow flies".
This rule seems a priori quite fair. Yet not everyone in France is in the same boat! If you live by the sea or near a border, the hundred-kilometre circle is reduced accordingly. Similarly, if you live near the edge of a large department, you can sometimes add a substantial part of the department lying more than a hundred kilometres from your home to this circle. We can therefore have some fun looking for those in France who are "most favoured" and "least favoured" by this rule. To do so, we need a map of France showing its municipalities, a precise interpretation of the 100 km rule, and a way to calculate distances "as the crow flies".
Setting the rules of the game
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