Arches is an area in the U.S. state of Utah that is one of the most famous national parks in North America and owes its fame to its fantastic sandstone arches. In spite of its comparatively modest size of three hundred square kilometres it boasts one of the most magnificent landscapes in the south west of the United States. The park's natural arches have become its unmistakable landmark and the impressive process of erosion that began in Prehistoric times demonstrates how even the hardest rock can be manipulated by the forces of nature. Landscape Arch is one of the park's most striking formations. With a span of around a hundred metres it is one of the largest of its kind in the world. Delicate Arch rises up grandly and majestically above Cache Valley and has become one of the most famous and most photographed stone arches in the world.For millions of years the freestanding Delicate Arch has defied both wind and weather but one day it will inevitably collapse due to its own weight. For in Arches National Park one thing is certain: even the hardest stone must sometimes give way to the persuasive power of erosion.