It may be hard to imagine giving up one of your precious days in Paris for an excursion outside the city - whether only a half-day or full day-trip - but there are few places that are definitely worth the sacrifice. In fact, some are so charming, they hardly feel like a sacrifice at all, and will only add to your vacation.
Château de Chantilly
France is full of stunning castles and the Château de Chantilly is no exception, making for a lovely afternoon escape from Paris.