We were pleasantly surprised by these gardens. As noted, your visit must start with a guided tour (in French). There is a booklet at the desk if you need an English translation - if you have time, read this ahead of your tour so you can look while on the tour. Our guide spoke clearly so we were able to follow most of the French. You are able to stay after the tour to extend your visit.
There are several parts to the garden intended to evoke different thoughts and feelings. I found them all visually interesting and an imaginative take on the formal garden with lovely views over the town from various points on the walk. I found the very last feature with the maps of the world's great rivers in bronze a bit weak and not up to the standard of the rest of the garden.
Don't come if you are expecting lots of flowers and be able to sit and have a picnic. It's not that kind of garden. Do come to see a different twist on a formal garden.
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