Mont St Michel is this magical place that is an island off the north coast of France approximately at the intersection of Brittany and Normandy with an Abbey built in 1020. It is only an island at high tide; the signs in the parking lot warn you about this. The slope of the ground is so small that you can actually see the the tide creeping in. Somewhere I have an 8mm movie of this from when we stayed there one night. (yeah, yeah, I should convert some of those movies into something viewable.) The article was about a project to reverse the silting up of the area that was going to make it a permanent piece of the mainland.
I found some nice pictures by Francis Toussaint.