A monastery and a town...surrounded by water?

I remember learning about this place when I was in middle school, and it fascinated me. Mont St. Michel is a monastery (still active today) that was built hundreds of years ago. It has become a bit commercialized - the monastery is at the top of the island, but you have to trek up the cobblestone roads filled wtih restaurants and souvenir shops to get there. It is a CLIMB - but the view is worth it. What's fascinating is that when the tide is low, you can easily access the island. However, when the tide is high, you can't reach it as it is surrounded by water. What a beautiful place!