I was just impressed by the 4k video in this appeal to help secure a chalk stream: https://youtu.be/kmRRn5l8GNo https://youtu.be/kmRRn5l8GNo It seems strange

I was just impressed by the 4k video in this appeal to help secure a chalk stream: https://youtu.be/kmRRn5l8GNo https://youtu.be/kmRRn5l8GNo It seems strange that nearly all are in the UK, is chalk just a geological formation in Northern Europe. Denmark, and Germany have chalk, as does France. I would have thought there would be a lot more in the world.