What is geologic heritage, you ask? In short, it "encompasses the significant geologic features, landforms, and landscapes characteristic of our Nation." The National Park Service has a special program to document these sites and to provide the public with resources about these unique destinations. The materials here are divided into four featured programs: Fossil Resources, Geologic Heritage Conservation, Park Geology Tour, and Cave and Karst Resources. Using the Park Geology Tour, visitors can search through thematic areas such as glaciers, fossils, and plate tectonics to find highlights from a vast array of National Park units. The Cave and Karst Resources program brings together resources on some of the over 4,900 caves in the National Park system, along with detailed photo galleries, newsletters, and brochures. Finally, under Fossil Resources visitors can find information about National Fossil Day and even helpful lesson plans for teachers.