On the main highway you'll know you've passed crosed over by a stone monument commemorating the partition and signs reading Bienvenue Partie Francaise in one direction, Welcome to Sint Maarten'' in the other that's all.
The stone monument is very small and easy to miss.  
mnli hypothesis: The stone monument is very small and easy to miss.   premise: On the main highway you'll know you've passed crosed over by a stone monument commemorating the partition and signs reading Bienvenue Partie Francaise in one direction, Welcome to Sint Maarten'' in the other that's all.