Environment Planet Earth 10 of the Most Colorful 'Painted' Hillsides in the World By Bryan Nelson Writer SUNY Oswego University of Houston Bryan Nelson is a science writer and award-winning documentary filmmaker with over a decade of experience covering technology, astronomy, medicine, and more. our editorial process Twitter Twitter Bryan Nelson Updated June 13, 2021 The stunning colors on display at Oregon's Painted Hills preserve geological evidence of 35 million years of climate change. Mitch Diamond / Getty Images Share Twitter Pinterest Email Environment Weather Outdoors Conservation Earth's geology isn't just responsible for shaping the world, it also helps give it color. Some of the best examples of this phenomenon are known as "painted" hills or mountains, where the varied colors of the planet's strata wash together to create colorful landscapes. Most painted mountains are built of layers of diverse sedimentary rocks, with bands of color exposed by millions of years of erosion. Others, however, are the result of repeated volcanic eruptions, when layers of lava flows cooled under unique circumstances and produced varied colors. In all cases, painted mountains are the result of entirely natural causes, and provide a window into how landscapes have changed throughout history. Here are 10 of the most spectacular painted hillsides in the world. 1 of 10 Zhangye National Geopark MelindaChan / Getty Images The Zhangye National Geopark in Gansu, China is home to a series of vibrant mountain ridges of many colors. The bands of red, blue, and orange striping the hillsides are composed of sandstone and calcium deposits that date back 120 million years. Wind and water erosion formed the peaks, and tectonic movement shifted the layers of sediment so that they cross the mountains at an angle. Also known as the Rainbow Mountains, the region is nearly devoid of vegetation, increasing the prominence of the colorful geological features. 2 of 10 Painted Hills AlbertoLoyo / Getty Images Part of the John Day Fossil Beds National Monument in Oregon, the Painted Hills are smooth, colorful hills composed of volcanic ash. The striking blood-red layers are due to bands of laterite, a soil type that is rich in iron and aluminum. The rock layers date back 40 million years, and help to reveal the ancient history of this region. Fossils found in the hills show that the landscape was once tropical and temperate, but has gradually become drier and colder over time. 3 of 10 Petrified Forest National Park Rebecca L. Latson / Getty Images Arizona's Petrified Forest National Park is home to multicolored mesas, hills, and bluffs in a section of the park called the Painted Desert. Stratified rock layers in the Chinle Formation, which dates back more than 200 million years, create the striped effect. As volcanoes erupted, lakes formed and evaporated, and temperatures fluctuated, the sediment layers of mudstone, siltstone, and shale formed a colorful record of these environmental changes. 4 of 10 Landmannalaugar Fibru Photography / Getty Images Landmannalaugar is a region of interior Iceland marked by hot springs, volcanoes, and multicolored mountains. The peaks here are primarily dark gray or black, but have streaks of blue, pink, and orange as well. The mountains are composed of rhyolite, an igneous volcanic rock that often appears glassy due to its high silica content. Frequent volcanic eruptions have formed multiple layers of rhyolite with different colors, according to its mineral content and rate of cooling. Landmannalaugar is part of the Fjallabak Nature Reserve. 5 of 10 Zion National Park The Good Brigade / Getty Images Utah's Zion National Park is a spectacle of towering cliffs, mesas, and natural arches of red, pink, and tan hues. The park is one of the most dramatic examples of the Navajo Sandstone formation, a 180 million-year-old geological feature from a time when most of the western United States was a continuous sand desert. Erosion from windswept sand and flowing water has revealed the full thickness of the Navajo Formation in Zion, where it spans more than 2,000 feet and forms immense, multicolored cliffs and canyons. 6 of 10 Painted Dunes Brad Miller / Getty Images The Painted Dunes are red, black, and tan hills that tell the story of volcanic eruptions in California's Lassen Volcanic National Park. The dunes lie in the shadow of Cinder Cone, an aptly named cinder cone volcano that was formed during two eruptions that occurred in the 1650s. While most of the surrounding landscape is dominated by black ash, the Painted Dunes are colorful. When Cinder Cone erupted, the volcanic ash that became the dunes interacted with still-hot lava flows, oxidizing the ash and producing the bright red colors seen today. 7 of 10 Painted Desert Southern Lightscapes-Australia / Getty Images Created by geological processes nearly 80 million years ago, the Painted Desert is a region of colorful hills in the desert of South Australia. The hills and mesas are composed of shale and range in color from white to black to red. The area is the remains of an ancient inland sea, which evaporated and left behind leached minerals. Since then, weathering and erosion have worn away layers of delicate rocks, revealing the vibrant geology. 8 of 10 Red Rocks JacobH / Getty Images The town of Sedona, Arizona is surrounded by red sandstone monoliths, buttes, and cliffs that are collectively known as the Red Rocks or Red Rock Country. The rock formations feature horizontal layers that vary in color from deep red to nearly white. The rocks are part of a geological formation called the Supai Group, deposited over the course of a 40 million-year period beginning about 310 million years ago. At that time, this region of Northern Arizona was a subtropical, coastal plain that was situated near the equator and likely had a similar appearance to the modern-day Sahara desert. 9 of 10 Badlands National Park Peter Unger / Getty Images South Dakota's Badlands National Park is a rugged landscape of vibrant rock spires and bluffs. The rock structures were formed by the deposition and erosion of soft, sedimentary rocks like sandstone, limestone, volcanic ash, and shale. The layers were deposited chronologically, and geologists believe the oldest layers date back 75 million years, while the most recent layer formed 30 million years ago. Each rock layer also corresponds to periods when the landscape varied remarkably. The Badlands were once covered by a vast inland sea, followed by a tropical floodplain, and then open grasslands. Today, the landscape is arid and largely devoid of vegetation. Due to the delicate nature of these sedimentary layers, the badlands erode quickly—about an inch a year. Geologists believe that within 500,000 years, the hills could be worn away entirely, leaving behind a flat, sandy landscape. 10 of 10 Vinicunca Piero M. Bianchi / Getty Images Vinicunca, also known as the Mountain of Seven Colors, is a colorful peak in the Peruvian Andes mountain range. The vertical multicolored stripes on the mountain are composed of various sedimentary rock layers. Some of the most prominent are iron-rich layers, which have turned red and green after exposure to oxygen and water. Until recently, Vinicunca was largely unknown because its slopes were obscured by icecaps year-round, but by 2015 it was a popular tourist destination. In 2018, the Peruvian government announced that the mountain would become a protected conservation area.