Hello, we (2 couples) will be visiting Paris early May (5/3-6). On our 1st day we will be touring around Saint Germain des Pres and Isle de Cite to see the exterior of Notre Dame and visit St Chapelle. It is my understanding you need a timed ticket. We really won't know exactly what time we will be arriving at St Chapelle. Can you buy a timed ticket last minute for St Chapelle? Or need I need to do that well ahead?
Also, how much time should we allow for seeing this? I'm sure there is a queue you have to wait in first plus tour time.
Would appreciate some input please. Merci beaucoup.