Glacial geology in Rocky Mountain National Park can be seen from the mountain peaks to the valley floors. Ice is a powerful sculptor of this natural environment and large masses of moving ice are the most powerful tools. Telltale marks of giant glaciers can be seen all throughout the park. Streams and glaciations during the Quaternary period cut through the older sediment, creating mesa tops and alluvial plains, and revealing the present Rocky Mountains.[61] The glaciation removed as much as 5,000 feet (1,500 m) of sedimentary rocks from earlier inland sea deposits. This erosion exposed the basement rock of the Ancestral Rockies. Evidence of the uplifting and erosion can be found on the way to Rocky Mountain National Park in the hogbacks of the Front Range foothills.[60] Many sedimentary rocks from the Paleozoic and Mesozoic eras exist in the basins surrounding the park.[62]