The Great Salt Lake is the second-largest saltwater lake in the world and the largest inland salt lake in North America. Located in western Utah, it is bordered by the Rocky Mountains to the east and desert landscapes to the west, and is composed of ten islands. The lake is also an important wildlife preserve, attracting millions of migratory birds each year. With a salinity level of up to 25%—second only to the Dead Sea—only highly salt-tolerant algae can survive in its waters, creating a unique and remarkable natural ecosystem.

Also known as the Grand Prismatic Hot Spring or the “Eye of the Earth,” Grand Prismatic Spring is located within Yellowstone National Park at coordinates 44.524569, -110.837975. With a diameter of approximately 100 meters, it is the largest hot spring in the United States and the third largest in the world. The spring measures about 75–91 meters in width, reaches a depth of 49 meters, and has water temperatures as high as 85°C. It discharges roughly 2,000 liters of 71°C water per minute and was first discovered by explorers in 1839. What makes the Grand Prismatic Spring truly remarkable is its vivid coloration, which changes with the seasons. In spring, the surface shifts from emerald green to brilliant orange-red hues. During midsummer, reduced chlorophyll levels cause the water to display vibrant shades of orange, red, or yellow. In winter, limited sunlight results in a deep, dark green appearance—creating a dramatic and ever-changing natural spectacle.

Also known as the “Artist Paint Pots,” Artist Paint Pots is named for its rich colors and ever-changing geothermal formations, making it one of Yellowstone’s most distinctive thermal areas. This site brings together four classic geothermal features—hot springs, mud pots, fumaroles, and small geysers. Walking along the boardwalk, visitors can observe bubbling mud pools, steaming vents releasing clouds of heat, and vivid mineral deposits that paint the landscape in striking hues. The entire area resembles a natural artist’s palette and stands as a representative highlight of Yellowstone’s geothermal wonders.

Old Faithful Geyser is one of the most famous geysers in Yellowstone National Park, renowned for its remarkably regular eruptions—hence the name “Old Faithful.” It was named during the Washburn–Langford–Doane Expedition in 1870 and is the first geyser in Yellowstone to have been officially named. Today, Old Faithful erupts approximately every 90 minutes. Each eruption lasts about 4–5 minutes, sending a powerful column of hot water soaring more than 40 meters (over 130 feet) into the air. Its consistent and uninterrupted activity creates a truly spectacular sight. Together with the nearby Old Faithful Inn, the geyser is part of the designated Old Faithful Historic District.

Morning Glory Pool is located at the far end of the Upper Geyser Basin in Yellowstone National Park. It is named for the vivid, morning-glory–like colors that appear along the pool’s rim, making it one of the park’s most iconic hot springs. The pool’s water displays a striking gradient, transitioning from deep blue at the center to shades of yellow and orange toward the edges. Under sunlight, these colors appear layered and highly photogenic. Fed continuously by underground high-temperature thermal springs, Morning Glory Pool maintains extremely hot water. Its unique coloration, combined with the surrounding rising steam and natural scenery, makes it a key highlight along the walking route through the Upper Geyser Basin.