This is the place I read about when I was a kid and dreamed of going there! What's great is that you can go there for a day from Paris and come back relatively inexpensively!
It is a very beautiful way to the abbey itself, you can find many figures of cows, which are painted in different ways, but in all cases very colorful.
I advise you to pay extra and take a walk around the abbey itself to experience the atmosphere of the Middle Ages. We were in autumn: there weren't a lot of people, it was still warm, but the weather helped create a good mood. You can also get a much better view of the surroundings from the castle.
Eating in popular places can be very expensive (we found dishes for 40 euros), but drinking coffee with pancakes is not very expensive.
There are a lot of souvenir shops on the streets under the abbey, if you are not interested in them, you need to climb a little higher, because huge crowds of people can gather locally below.
I also advise you to go around the whole structure: you can find beautiful shells and take beautiful photos. And with a good tide, you can almost walk to the neighboring island without getting wet.
This meeting was a long time ago, but it leaves an amazing aftertaste of something magical and mysterious! It's great to remember this majestic view, delicious wind, the warmth of the sun and the endless horizon, seagulls… I managed to touch it and take away a piece of it in my memory and feelings!
It is a very beautiful place and even a lot of tourists can enjoy the beauty and monumentality. The road from the bus stop to the castle is worth walking. Admire the castle from different distances, look for sheep. Wander around the field with a view of the castle.