Boulder clay at Robin Hoods Bay

 I was intrigued by the variety of igneous pebbles on the beach at Robin Hoods Bay in Yorkshire, which is in a resolutely sedimentary area. I also found this lovely piece of quartzite. I know that the nearest quartzite must be in the north of Scotland. Then I looked at the cliff behind me...

It is boulder clay deposited by a glacier. The stones in it are all quite angular, showing that they have not been subject to bashing during transportation by water. I have read that they can use the rocks in the boulder clay to plot the courses of ancient glaciers. Looks like there could have been a flow from Scotland.