Landforms shaped by the removal of rock through weathering, running water, wind, waves or the dissolution of soluble rock, following the erosional and karst divisions of standard geomorphology. Includes fluvial and aeolian erosional landforms cut by rivers, wind and rain into arches, canyons, hoodoos and slot canyons (Antelope Canyon, Bryce Canyon Amphitheater, Delicate Arch, Monument Valley, The Wave), and karst landforms produced by the dissolution of limestone or other soluble rock into towers, potholes, sea stacks and pinnacle forests (Ha Long Bay, Li River Karst, Stone Forest Shilin, Tsingy de Bemaraha). Belongs here: any formation whose defining shape comes from the removal of material by water, wind or dissolution acting on rock already in place. Does not belong here: a formation built up by the deposition of new material (Sedimentary and Stratigraphic Formations) or shaped directly by an eruption or intrusion of molten rock (Volcanic Formations).