Even on a tight schedule, Giverny Day Trip (Monet's Garden) earns the hours.
Allow Half to full day.
The garden that Monet painted obsessively, with the Japanese bridge and lily pond, is genuinely transporting in spring and summer. It's seasonal (closed in winter) and a real trek (~1 hr+ each way), but on a sunny day it's a highlight. Go early — it gets busy by midday.