The only worthwhile beach area is near Tartane on the mid-island Caravelle peninsula, where there's also a park with walking trails.
Tartane has the only worthwhile beach in the area.  
mnli hypothesis: Tartane has the only worthwhile beach in the area.   premise: The only worthwhile beach area is near Tartane on the mid-island Caravelle peninsula, where there's also a park with walking trails.